diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 50abc36..cc250db 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -114,6 +114,19 @@ jobs:
           VERSION: ${{ steps.version.outputs.VERSION }}
         run: gh release upload "v$env:VERSION" releases/PlanViewer.Ssms.vsix releases/InstallSsmsExtension.exe --clobber
 
+      # Publish to the SSMS Gallery (https://ssmsgallery.azurewebsites.net, issue 343).
+      # The gallery extracts version/description from the vsixmanifest, so the
+      # upload filename is irrelevant. continue-on-error: a gallery outage must
+      # never fail the release. bash so `curl` is curl.exe, not the pwsh alias.
+      - name: Publish SSMS extension to SSMS Gallery
+        if: steps.ssms.outputs.BUILT == 'true'
+        continue-on-error: true
+        shell: bash
+        run: |
+          echo "Uploading PlanViewer.Ssms.vsix to the SSMS Gallery..."
+          curl -sS -f "https://ssmsgallery.azurewebsites.net/api/upload" \
+            -F "file=@releases/PlanViewer.Ssms.vsix"
+
       # ── SignPath code signing (Windows only, skipped if secret not configured) ──
       - name: Check if signing is configured
         id: signing
diff --git a/src/Directory.Build.props b/src/Directory.Build.props
index 2b7cd2c..23fe79c 100644
--- a/src/Directory.Build.props
+++ b/src/Directory.Build.props
@@ -15,7 +15,7 @@
     Tests and server/ projects are outside src/ and are unaffected.
   -->
   <PropertyGroup>
-    <Version>1.11.2</Version>
+    <Version>1.12.0</Version>
     <Authors>Erik Darling</Authors>
     <Company>Darling Data LLC</Company>
     <Product>Performance Studio</Product>
diff --git a/src/PlanViewer.App/Controls/QuerySessionControl.Format.cs b/src/PlanViewer.App/Controls/QuerySessionControl.Format.cs
index 9ead789..eea3f84 100644
--- a/src/PlanViewer.App/Controls/QuerySessionControl.Format.cs
+++ b/src/PlanViewer.App/Controls/QuerySessionControl.Format.cs
@@ -86,9 +86,7 @@ private async void Format_Click(object? sender, RoutedEventArgs e)
 
         try
         {
-            var settings = SqlFormatSettingsService.Load(out var loadError);
-            if (loadError != null)
-                SetStatus("Warning: using default format settings (load failed)");
+            var settings = AppSettingsService.Load().FormatOptions ?? new SqlFormatSettings();
 
             var (formatted, errors) = await Task.Run(() => SqlFormattingService.Format(sql, settings));
 
@@ -150,10 +148,4 @@ private async void Format_Click(object? sender, RoutedEventArgs e)
             FormatButton.IsEnabled = true;
         }
     }
-
-    private void FormatOptions_Click(object? sender, RoutedEventArgs e)
-    {
-        var dialog = new Dialogs.FormatOptionsWindow();
-        dialog.ShowDialog(GetParentWindow());
-    }
 }
diff --git a/src/PlanViewer.App/Controls/QuerySessionControl.axaml b/src/PlanViewer.App/Controls/QuerySessionControl.axaml
index a9aefad..f651f35 100644
--- a/src/PlanViewer.App/Controls/QuerySessionControl.axaml
+++ b/src/PlanViewer.App/Controls/QuerySessionControl.axaml
@@ -92,10 +92,6 @@
                             Height="28" Padding="10,0" FontSize="12"
                             Theme="{StaticResource AppButton}"
                             ToolTip.Tip="Format the SQL query"/>
-                    <Button x:Name="FormatOptionsButton" Content="&#x2699; Format Options" Click="FormatOptions_Click"
-                            Height="28" Padding="10,0" FontSize="12"
-                            Theme="{StaticResource AppButton}"
-                            ToolTip.Tip="Configure SQL formatting options"/>
                 </WrapPanel>
             </DockPanel>
         </Border>
diff --git a/src/PlanViewer.App/Controls/QueryStoreGridControl.axaml.cs b/src/PlanViewer.App/Controls/QueryStoreGridControl.axaml.cs
index 0a7b1dc..efcca82 100644
--- a/src/PlanViewer.App/Controls/QueryStoreGridControl.axaml.cs
+++ b/src/PlanViewer.App/Controls/QueryStoreGridControl.axaml.cs
@@ -61,8 +61,23 @@ public QueryStoreGridControl(ServerConnection serverConnection, ICredentialServi
         _database = initialDatabase;
         _connectionString = serverConnection.GetConnectionString(credentialService, initialDatabase);
         _waitStatsSupported = supportsWaitStats;
-        _slicerDaysBack = AppSettingsService.Load().QueryStoreSlicerDays;
+
+        var userSettings = AppSettingsService.Load();
+        _slicerDaysBack = userSettings.QueryStoreSlicerDays;
+
         InitializeComponent();
+
+        // Apply user defaults to UI controls
+        TopNBox.Value = userSettings.QueryStoreTopLimit;
+        SelectComboByTag(OrderByBox, userSettings.QueryStoreDefaultMetric);
+        SelectComboByTag(GroupByBox, userSettings.QueryStoreDefaultGroupBy switch
+        {
+            "QueryHash" => "query-hash",
+            "Module" => "module",
+            "None" => "none",
+            _ => "query-hash"
+        });
+
         ResultsGrid.ItemsSource = _filteredRows;
         Helpers.DataGridBehaviors.Attach(ResultsGrid);
         EnsureFilterPopup();
@@ -227,6 +242,21 @@ private static readonly (string ColumnId, Func<QueryStoreRow, double> Accessor)[
         ["AvgMemSort"]         = "AvgMemory",
     };
 
+    private static void SelectComboByTag(ComboBox box, string tag)
+    {
+        for (int i = 0; i < box.Items.Count; i++)
+        {
+            if (box.Items[i] is ComboBoxItem item && item.Tag?.ToString() == tag)
+            {
+                box.SelectedIndex = i;
+                return;
+            }
+        }
+        // Unknown tag — fall back to the first item so the combo is never empty
+        if (box.Items.Count > 0)
+            box.SelectedIndex = 0;
+    }
+
 
 }
 
diff --git a/src/PlanViewer.App/Controls/QueryStoreHistoryControl.axaml.cs b/src/PlanViewer.App/Controls/QueryStoreHistoryControl.axaml.cs
index b674825..293a1d8 100644
--- a/src/PlanViewer.App/Controls/QueryStoreHistoryControl.axaml.cs
+++ b/src/PlanViewer.App/Controls/QueryStoreHistoryControl.axaml.cs
@@ -296,7 +296,14 @@ private async System.Threading.Tasks.Task LoadHistoryAsync()
 	private void BuildColorMap()
 	{
 		_planHashColorMap.Clear();
-		var hashes = _historyData.Select(r => r.QueryPlanHash).Distinct().OrderBy(h => h).ToList();
+		var maxPlans = Services.AppSettingsService.Load().QueryHistoryMaxPlans;
+		var hashes = _historyData
+			.GroupBy(r => r.QueryPlanHash)
+			.OrderByDescending(g => g.Sum(r => r.CountExecutions))
+			.Take(maxPlans)
+			.Select(g => g.Key)
+			.OrderBy(h => h)
+			.ToList();
 		for (int i = 0; i < hashes.Count; i++)
 			_planHashColorMap[hashes[i]] = PlanColors[i % PlanColors.Length];
 	}
diff --git a/src/PlanViewer.App/Controls/QueryStoreOverviewControl.axaml.cs b/src/PlanViewer.App/Controls/QueryStoreOverviewControl.axaml.cs
index 040b702..9fa2d43 100644
--- a/src/PlanViewer.App/Controls/QueryStoreOverviewControl.axaml.cs
+++ b/src/PlanViewer.App/Controls/QueryStoreOverviewControl.axaml.cs
@@ -12,6 +12,7 @@
 using Avalonia.Interactivity;
 using Avalonia.Media;
 using Avalonia.Threading;
+using PlanViewer.App.Services;
 using PlanViewer.Core.Interfaces;
 using PlanViewer.Core.Models;
 using PlanViewer.Core.Services;
@@ -38,18 +39,8 @@ public partial class QueryStoreOverviewControl : UserControl
     private DateTime _slicerEndUtc;
     private int _daysBack = 30;
 
-    // Color palette for databases (minimizes color dispersion)
-    private static readonly Color[] Palette = new[]
-    {
-        Color.Parse("#2EAEF1"), // blue
-        Color.Parse("#F2994A"), // orange
-        Color.Parse("#27AE60"), // green
-        Color.Parse("#9B51E0"), // purple
-        Color.Parse("#EB5757"), // red
-        Color.Parse("#F2C94C"), // yellow
-        Color.Parse("#56CCF2"), // light blue
-        Color.Parse("#BB6BD9"), // violet
-    };
+    // Color palette for databases — loaded from user settings
+    private readonly Color[] _palette;
 
     private static readonly Color OthersColor = Color.Parse("#555555");
 
@@ -69,13 +60,21 @@ public class DrillDownEventArgs(string database, DateTime startUtc, DateTime end
     public event EventHandler<DrillDownEventArgs>? DrillDownRequested;
 
     public QueryStoreOverviewControl(ServerConnection serverConnection,
-        ICredentialService credentialService, int maxDop = 8, int topN = 4, bool supportsWaitStats = true)
+        ICredentialService credentialService, int maxDop = 8, int? topN = null, bool supportsWaitStats = true)
     {
         _serverConnection = serverConnection;
         _credentialService = credentialService;
         _masterConnectionString = serverConnection.GetConnectionString(credentialService, "master");
         _maxDop = maxDop;
-        _topN = topN;
+
+        var userSettings = AppSettingsService.Load();
+        _topN = topN ?? userSettings.MultiQsTopDbCount;
+        _palette = userSettings.MultiQsTopDbColors
+            .Select(hex => { try { return Color.Parse(hex); } catch { return Color.Parse("#555555"); } })
+            .ToArray();
+        if (_palette.Length == 0)
+            _palette = AppSettingsService.DefaultTopDbColors.Select(hex => Color.Parse(hex)).ToArray();
+
         _supportsWaitStats = supportsWaitStats;
         _slicerEndUtc = DateTime.UtcNow;
         _slicerStartUtc = _slicerEndUtc.AddHours(-24);
@@ -668,8 +667,8 @@ private void DrawBarCards()
             .Select(m => m.DatabaseName)
             .ToList();
         var topDbs = ranked.Take(_topN).ToList();
-        for (int i = 0; i < topDbs.Count && i < Palette.Length; i++)
-            _dbColorMap[topDbs[i]] = Palette[i];
+        for (int i = 0; i < topDbs.Count && i < _palette.Length; i++)
+            _dbColorMap[topDbs[i]] = _palette[i];
 
         DrawMetricRow(TotalMetricsGrid, isTotal: true, topDbs);
         DrawMetricRow(AvgMetricsGrid, isTotal: false, topDbs);
diff --git a/src/PlanViewer.App/Controls/TimeRangeSlicerControl.axaml.cs b/src/PlanViewer.App/Controls/TimeRangeSlicerControl.axaml.cs
index 7edfdf0..1389be0 100644
--- a/src/PlanViewer.App/Controls/TimeRangeSlicerControl.axaml.cs
+++ b/src/PlanViewer.App/Controls/TimeRangeSlicerControl.axaml.cs
@@ -8,6 +8,7 @@
 using Avalonia.Interactivity;
 using Avalonia.Media;
 using Avalonia.Threading;
+using PlanViewer.App.Services;
 using PlanViewer.Core.Models;
 using PlanViewer.Core.Services;
 
@@ -52,13 +53,14 @@ private enum DragMode { None, MoveRange, DragStart, DragEnd, SelectRect }
     private double _selectRectOriginX;   // canvas-x where drag-select started
     private double _selectRectCurrentX;  // canvas-x of current pointer during drag-select
 
-    private string _activeFilterTag = "24"; // tag of the currently active quick-filter button
+    private string _activeFilterTag; // tag from user settings
     private DispatcherTimer? _rangeChangedDebounce;
 
     public event EventHandler<TimeRangeChangedEventArgs>? RangeChanged;
 
     public TimeRangeSlicerControl()
     {
+        _activeFilterTag = AppSettingsService.Load().QueryStoreDefaultTimeRange;
         InitializeComponent();
         SlicerBorder.SizeChanged += (_, _) => Redraw();
         SlicerCanvas.Focusable = true;
@@ -80,13 +82,13 @@ public void LoadData(List<QueryStoreTimeSlice> data, string metric,
         }
         else
         {
-            // Default selection: last 24 hours
+            // Default selection from user settings
             _rangeEnd = 1.0;
-            _activeFilterTag = "24";
+            var defaultHours = int.TryParse(_activeFilterTag, out var h) ? h : 24;
             if (_data.Count >= 2)
             {
                 var last = _data[^1].IntervalStartUtc.AddHours(1);
-                var start24h = last.AddHours(-24);
+                var start24h = last.AddHours(-defaultHours);
                 _rangeStart = GetNormFromDateTime(start24h);
             }
             else
diff --git a/src/PlanViewer.App/Dialogs/FormatOptionRow.cs b/src/PlanViewer.App/Dialogs/FormatOptionRow.cs
new file mode 100644
index 0000000..87c63b5
--- /dev/null
+++ b/src/PlanViewer.App/Dialogs/FormatOptionRow.cs
@@ -0,0 +1,56 @@
+using System.ComponentModel;
+using System.Reflection;
+
+namespace PlanViewer.App.Dialogs;
+
+internal class FormatOptionRow : INotifyPropertyChanged
+{
+	private string _currentValue = "";
+	private bool _boolValue;
+
+	public string Name { get; set; } = "";
+
+	public bool IsBool { get; set; }
+
+	public bool BoolValue
+	{
+		get => _boolValue;
+		set
+		{
+			if (_boolValue == value) return;
+			_boolValue = value;
+			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(BoolValue)));
+			// Keep CurrentValue in sync for serialization
+			if (IsBool)
+			{
+				_currentValue = value.ToString();
+				PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(CurrentValue)));
+			}
+		}
+	}
+
+	public bool DefaultBoolValue { get; set; }
+
+	public string[]? ChoiceOptions { get; set; }
+
+	public bool IsChoice => ChoiceOptions != null;
+
+	public bool IsText => !IsBool && !IsChoice;
+
+	public string CurrentValue
+	{
+		get => _currentValue;
+		set
+		{
+			if (_currentValue == value) return;
+			_currentValue = value;
+			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(CurrentValue)));
+		}
+	}
+
+	public string DefaultValue { get; set; } = "";
+
+	internal PropertyInfo PropertyInfo { get; set; } = null!;
+
+	public event PropertyChangedEventHandler? PropertyChanged;
+}
diff --git a/src/PlanViewer.App/Dialogs/FormatOptionsWindow.axaml b/src/PlanViewer.App/Dialogs/FormatOptionsWindow.axaml
deleted file mode 100644
index 78594a4..0000000
--- a/src/PlanViewer.App/Dialogs/FormatOptionsWindow.axaml
+++ /dev/null
@@ -1,121 +0,0 @@
-<Window xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:dialogs="using:PlanViewer.App.Dialogs"
-        x:Class="PlanViewer.App.Dialogs.FormatOptionsWindow"
-        Title="SQL Format Options"
-        Width="650" Height="580"
-        MinWidth="520" MinHeight="400"
-        Background="{DynamicResource BackgroundBrush}"
-        Foreground="{DynamicResource ForegroundBrush}"
-        WindowStartupLocation="CenterOwner">
-
-    <Window.Styles>
-        <Style Selector="ToggleSwitch">
-            <Setter Property="OnContent" Value=""/>
-            <Setter Property="OffContent" Value=""/>
-            <Setter Property="MinWidth" Value="0"/>
-            <Setter Property="MinHeight" Value="0"/>
-            <Setter Property="Padding" Value="0"/>
-            <Setter Property="Margin" Value="0"/>
-            <Setter Property="VerticalAlignment" Value="Center"/>
-            <Setter Property="RenderTransformOrigin" Value="0%,50%"/>
-            <Setter Property="RenderTransform" Value="scale(0.75)"/>
-        </Style>
-        <Style Selector="ToggleSwitch:checked /template/ Border#SwitchKnobBounds">
-            <Setter Property="Background" Value="{DynamicResource AccentBrush}"/>
-            <Setter Property="BorderBrush" Value="{DynamicResource AccentBrush}"/>
-        </Style>
-        <Style Selector="ToggleSwitch:checked /template/ Border#OuterBorder">
-            <Setter Property="BorderBrush" Value="{DynamicResource AccentBrush}"/>
-        </Style>
-    </Window.Styles>
-
-    <Grid RowDefinitions="*,Auto" Margin="12">
-        <DataGrid x:Name="OptionsGrid" Grid.Row="0"
-                  x:DataType="dialogs:FormatOptionRow"
-                  AutoGenerateColumns="False"
-                  CanUserReorderColumns="False"
-                  CanUserSortColumns="False"
-                  HeadersVisibility="Column"
-                  GridLinesVisibility="Horizontal"
-                  IsReadOnly="False"
-                  Background="{DynamicResource BackgroundBrush}"
-                  Foreground="{DynamicResource ForegroundBrush}"
-                  Margin="0,0,0,12">
-            <DataGrid.Columns>
-                <DataGridTextColumn Header="Parameter" Binding="{Binding Name}" IsReadOnly="True" Width="2*"/>
-                <DataGridTemplateColumn Header="Current Value" Width="*">
-                    <DataGridTemplateColumn.CellTemplate>
-                        <DataTemplate x:DataType="dialogs:FormatOptionRow">
-                            <Panel>
-                                <ToggleSwitch IsChecked="{Binding BoolValue}"
-                                              IsVisible="{Binding IsBool}"
-                                              VerticalAlignment="Center"
-                                              Margin="4,0"/>
-                                <ComboBox ItemsSource="{Binding ChoiceOptions}"
-                                          SelectedItem="{Binding CurrentValue}"
-                                          IsVisible="{Binding IsChoice}"
-                                          VerticalAlignment="Center"
-                                          MinHeight="0" Height="26" FontSize="12"
-                                          Margin="4,0"/>
-                                <TextBlock Text="{Binding CurrentValue}"
-                                           IsVisible="{Binding IsText}"
-                                           VerticalAlignment="Center"
-                                           Margin="8,0"/>
-                            </Panel>
-                        </DataTemplate>
-                    </DataGridTemplateColumn.CellTemplate>
-                    <DataGridTemplateColumn.CellEditingTemplate>
-                        <DataTemplate x:DataType="dialogs:FormatOptionRow">
-                            <Panel>
-                                <ToggleSwitch IsChecked="{Binding BoolValue}"
-                                              IsVisible="{Binding IsBool}"
-                                              VerticalAlignment="Center"
-                                              Margin="4,0"/>
-                                <ComboBox ItemsSource="{Binding ChoiceOptions}"
-                                          SelectedItem="{Binding CurrentValue}"
-                                          IsVisible="{Binding IsChoice}"
-                                          VerticalAlignment="Center"
-                                          MinHeight="0" Height="26" FontSize="12"
-                                          Margin="4,0"/>
-                                <TextBox Text="{Binding CurrentValue}"
-                                         IsVisible="{Binding IsText}"
-                                         VerticalAlignment="Center"
-                                         Margin="4,0"/>
-                            </Panel>
-                        </DataTemplate>
-                    </DataGridTemplateColumn.CellEditingTemplate>
-                </DataGridTemplateColumn>
-                <DataGridTemplateColumn Header="Default Value" IsReadOnly="True" Width="*">
-                    <DataGridTemplateColumn.CellTemplate>
-                        <DataTemplate x:DataType="dialogs:FormatOptionRow">
-                            <Panel>
-                                <ToggleSwitch IsChecked="{Binding DefaultBoolValue}"
-                                              IsVisible="{Binding IsBool}"
-                                              IsEnabled="False"
-                                              VerticalAlignment="Center"
-                                              Margin="4,0"/>
-                                <TextBlock Text="{Binding DefaultValue}"
-                                           IsVisible="{Binding !IsBool}"
-                                           VerticalAlignment="Center"
-                                           Margin="8,0"/>
-                                <!-- Choice defaults shown as text -->
-                            </Panel>
-                        </DataTemplate>
-                    </DataGridTemplateColumn.CellTemplate>
-                </DataGridTemplateColumn>
-            </DataGrid.Columns>
-        </DataGrid>
-        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8">
-            <Button x:Name="RevertButton" Content="Revert to Default" Click="Revert_Click"
-                    Height="32" Padding="16,0" FontSize="12"
-                    Theme="{StaticResource AppButton}"/>
-            <Button x:Name="SaveButton" Content="Save" Click="Save_Click"
-                    Height="32" Padding="16,0" FontSize="12"
-                    Theme="{StaticResource AppButton}"/>
-            <Button x:Name="CloseButton" Content="Close" Click="Close_Click"
-                    Height="32" Padding="16,0" FontSize="12"
-                    Theme="{StaticResource AppButton}"/>
-        </StackPanel>
-    </Grid>
-</Window>
diff --git a/src/PlanViewer.App/Dialogs/FormatOptionsWindow.axaml.cs b/src/PlanViewer.App/Dialogs/FormatOptionsWindow.axaml.cs
deleted file mode 100644
index 60cb457..0000000
--- a/src/PlanViewer.App/Dialogs/FormatOptionsWindow.axaml.cs
+++ /dev/null
@@ -1,342 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Collections.ObjectModel;
-using System.ComponentModel;
-using System.Diagnostics;
-using System.Linq;
-using System.Reflection;
-using System.Text;
-using System.Threading.Tasks;
-using Avalonia.Controls;
-using Avalonia.Interactivity;
-using Avalonia.Media;
-using PlanViewer.App.Services;
-
-namespace PlanViewer.App.Dialogs;
-
-public partial class FormatOptionsWindow : Window
-{
-    private readonly ObservableCollection<FormatOptionRow> _rows = new();
-    private readonly SqlFormatSettings _defaults = new();
-
-    private bool _isDirty;
-
-    public FormatOptionsWindow()
-    {
-        InitializeComponent();
-        LoadSettings();
-    }
-
-    // Explicit ordering — reflection doesn't guarantee declaration order
-    private static readonly string[] PropertyOrder =
-    [
-        "KeywordCasing", "SqlVersion", "IndentationSize",
-        "AlignClauseBodies", "AlignColumnDefinitionFields", "AlignSetClauseItem",
-        "AsKeywordOnOwnLine", "IncludeSemicolons",
-        "IndentSetClause", "IndentViewBody",
-        "MultilineInsertSourcesList", "MultilineInsertTargetsList",
-        "MultilineSelectElementsList", "MultilineSetClauseItems",
-        "MultilineViewColumnsList", "MultilineWherePredicatesList",
-        "NewLineBeforeCloseParenthesisInMultilineList",
-        "NewLineBeforeFromClause", "NewLineBeforeGroupByClause",
-        "NewLineBeforeHavingClause", "NewLineBeforeJoinClause",
-        "NewLineBeforeOffsetClause", "NewLineBeforeOpenParenthesisInMultilineList",
-        "NewLineBeforeOrderByClause", "NewLineBeforeOutputClause",
-        "NewLineBeforeWhereClause", "NewLineBeforeWindowClause",
-    ];
-
-    private static string SplitPascalCase(string name)
-    {
-        var sb = new StringBuilder(name.Length + 8);
-        for (int i = 0; i < name.Length; i++)
-        {
-            var c = name[i];
-            if (i > 0 && char.IsUpper(c) && !char.IsUpper(name[i - 1]))
-                sb.Append(' ');
-            sb.Append(c);
-        }
-        return sb.ToString();
-    }
-
-    private static readonly Dictionary<string, string[]> ChoiceOptionsMap = new()
-    {
-        ["KeywordCasing"] = ["Uppercase", "Lowercase", "PascalCase"],
-        ["SqlVersion"] = ["80", "90", "100", "110", "120", "130", "140", "150", "160", "170"],
-    };
-
-    private void LoadSettings()
-    {
-        var current = SqlFormatSettingsService.Load(out var loadError);
-        if (loadError != null)
-            ShowErrorPopup("Load Error", loadError);
-        _rows.Clear();
-
-        var props = typeof(SqlFormatSettings).GetProperties(BindingFlags.Public | BindingFlags.Instance)
-            .ToDictionary(p => p.Name);
-
-        foreach (var name in PropertyOrder)
-        {
-            if (!props.TryGetValue(name, out var prop))
-                continue;
-
-            var currentVal = prop.GetValue(current);
-            var defaultVal = prop.GetValue(_defaults);
-            var isBool = prop.PropertyType == typeof(bool);
-
-            ChoiceOptionsMap.TryGetValue(prop.Name, out var choiceOptions);
-
-            _rows.Add(new FormatOptionRow
-            {
-                Name = SplitPascalCase(prop.Name),
-                CurrentValue = currentVal?.ToString() ?? "",
-                DefaultValue = defaultVal?.ToString() ?? "",
-                IsBool = isBool,
-                BoolValue = isBool && currentVal is true,
-                DefaultBoolValue = isBool && defaultVal is true,
-                ChoiceOptions = choiceOptions,
-                PropertyInfo = prop
-            });
-        }
-
-        OptionsGrid.ItemsSource = _rows;
-
-        // Track changes for dirty-state prompt
-        foreach (var row in _rows)
-            row.PropertyChanged += (_, _) => _isDirty = true;
-    }
-
-    private void Save_Click(object? sender, RoutedEventArgs e)
-    {
-        var settings = new SqlFormatSettings();
-
-        foreach (var row in _rows)
-        {
-            try
-            {
-                var prop = row.PropertyInfo;
-                object? value;
-
-                if (prop.PropertyType == typeof(bool))
-                    value = row.BoolValue;
-                else if (prop.PropertyType == typeof(int))
-                {
-                    if (!int.TryParse(row.CurrentValue, out var intVal))
-                    {
-                        Debug.WriteLine($"FormatOptions: invalid int value '{row.CurrentValue}' for {row.Name}, using default");
-                        continue;
-                    }
-                    value = intVal;
-                }
-                else
-                    value = row.CurrentValue;
-
-                prop.SetValue(settings, value);
-            }
-            catch (Exception ex)
-            {
-                Debug.WriteLine($"FormatOptions: failed to set {row.Name}: {ex.Message}");
-            }
-        }
-
-        if (!SqlFormatSettingsService.Save(settings, out var saveError))
-        {
-            ShowErrorPopup("Save Error", saveError!);
-            return;
-        }
-        _isDirty = false;
-        Close();
-    }
-
-    private void Revert_Click(object? sender, RoutedEventArgs e)
-    {
-        foreach (var row in _rows)
-        {
-            row.CurrentValue = row.DefaultValue;
-            if (row.IsBool)
-                row.BoolValue = row.DefaultBoolValue;
-        }
-    }
-
-    private void ShowErrorPopup(string title, string message)
-    {
-        var dialog = new Window
-        {
-            Title = title,
-            Width = 480,
-            Height = 220,
-            WindowStartupLocation = WindowStartupLocation.CenterOwner,
-            Background = (IBrush)this.FindResource("BackgroundBrush")!,
-            Foreground = (IBrush)this.FindResource("ForegroundBrush")!,
-            Content = new StackPanel
-            {
-                Margin = new Avalonia.Thickness(20),
-                Children =
-                {
-                    new TextBlock
-                    {
-                        Text = message,
-                        TextWrapping = TextWrapping.Wrap,
-                        FontSize = 13
-                    }
-                }
-            }
-        };
-        dialog.ShowDialog(this);
-    }
-
-    private void Close_Click(object? sender, RoutedEventArgs e)
-    {
-        TryClose();
-    }
-
-    protected override void OnClosing(WindowClosingEventArgs e)
-    {
-        if (_isDirty)
-        {
-            e.Cancel = true;
-            TryClose();
-            return;
-        }
-        base.OnClosing(e);
-    }
-
-    private async void TryClose()
-    {
-        if (!_isDirty)
-        {
-            _isDirty = false; // prevent re-entry
-            Close();
-            return;
-        }
-
-        var result = await ShowDiscardDialog();
-        if (result)
-        {
-            _isDirty = false;
-            Close();
-        }
-    }
-
-    private async Task<bool> ShowDiscardDialog()
-    {
-        var tcs = new TaskCompletionSource<bool>();
-
-        var dialog = new Window
-        {
-            Title = "Unsaved Changes",
-            Width = 360,
-            Height = 160,
-            MinWidth = 360,
-            MinHeight = 160,
-            WindowStartupLocation = WindowStartupLocation.CenterOwner,
-            Background = (IBrush)this.FindResource("BackgroundBrush")!,
-            Foreground = (IBrush)this.FindResource("ForegroundBrush")!,
-            Content = new StackPanel
-            {
-                Margin = new Avalonia.Thickness(20),
-                Children =
-                {
-                    new TextBlock
-                    {
-                        Text = "You have unsaved changes. Discard them?",
-                        FontSize = 13,
-                        TextWrapping = TextWrapping.Wrap,
-                        Margin = new Avalonia.Thickness(0, 0, 0, 16)
-                    }
-                }
-            }
-        };
-
-        var discardBtn = new Button
-        {
-            Content = "Discard",
-            Height = 32, Width = 90,
-            Padding = new Avalonia.Thickness(16, 0),
-            FontSize = 12,
-            HorizontalContentAlignment = Avalonia.Layout.HorizontalAlignment.Center,
-            VerticalContentAlignment = Avalonia.Layout.VerticalAlignment.Center,
-            Theme = (Avalonia.Styling.ControlTheme)this.FindResource("AppButton")!
-        };
-
-        var cancelBtn = new Button
-        {
-            Content = "Cancel",
-            Height = 32, Width = 90,
-            Padding = new Avalonia.Thickness(16, 0),
-            FontSize = 12,
-            Margin = new Avalonia.Thickness(8, 0, 0, 0),
-            HorizontalContentAlignment = Avalonia.Layout.HorizontalAlignment.Center,
-            VerticalContentAlignment = Avalonia.Layout.VerticalAlignment.Center,
-            Theme = (Avalonia.Styling.ControlTheme)this.FindResource("AppButton")!
-        };
-
-        var buttonPanel = new StackPanel
-        {
-            Orientation = Avalonia.Layout.Orientation.Horizontal,
-            HorizontalAlignment = Avalonia.Layout.HorizontalAlignment.Right
-        };
-        buttonPanel.Children.Add(discardBtn);
-        buttonPanel.Children.Add(cancelBtn);
-
-        ((StackPanel)dialog.Content!).Children.Add(buttonPanel);
-
-        discardBtn.Click += (_, _) => { tcs.TrySetResult(true); dialog.Close(); };
-        cancelBtn.Click += (_, _) => { tcs.TrySetResult(false); dialog.Close(); };
-        dialog.Closing += (_, _) => tcs.TrySetResult(false);
-
-        await dialog.ShowDialog(this);
-        return await tcs.Task;
-    }
-}
-
-public class FormatOptionRow : INotifyPropertyChanged
-{
-    private string _currentValue = "";
-    private bool _boolValue;
-
-    public string Name { get; set; } = "";
-
-    public bool IsBool { get; set; }
-
-    public bool BoolValue
-    {
-        get => _boolValue;
-        set
-        {
-            if (_boolValue == value) return;
-            _boolValue = value;
-            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(BoolValue)));
-            // Keep CurrentValue in sync for serialization
-            if (IsBool)
-            {
-                _currentValue = value.ToString();
-                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(CurrentValue)));
-            }
-        }
-    }
-
-    public bool DefaultBoolValue { get; set; }
-
-    public string[]? ChoiceOptions { get; set; }
-
-    public bool IsChoice => ChoiceOptions != null;
-
-    public bool IsText => !IsBool && !IsChoice;
-
-    public string CurrentValue
-    {
-        get => _currentValue;
-        set
-        {
-            if (_currentValue == value) return;
-            _currentValue = value;
-            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(CurrentValue)));
-        }
-    }
-
-    public string DefaultValue { get; set; } = "";
-
-    internal PropertyInfo PropertyInfo { get; set; } = null!;
-
-    public event PropertyChangedEventHandler? PropertyChanged;
-}
diff --git a/src/PlanViewer.App/Dialogs/QueryStoreHistoryWindow.axaml.cs b/src/PlanViewer.App/Dialogs/QueryStoreHistoryWindow.axaml.cs
index ee13bf8..840d844 100644
--- a/src/PlanViewer.App/Dialogs/QueryStoreHistoryWindow.axaml.cs
+++ b/src/PlanViewer.App/Dialogs/QueryStoreHistoryWindow.axaml.cs
@@ -1,6 +1,7 @@
 using System;
 using Avalonia.Controls;
 using PlanViewer.App.Controls;
+using PlanViewer.App.Services;
 
 namespace PlanViewer.App.Dialogs;
 
@@ -18,15 +19,19 @@ public QueryStoreHistoryWindow()
 
 	public QueryStoreHistoryWindow(string connectionString, string queryHash,
 		string queryText, string database,
-		string initialMetricTag = "AvgCpuMs",
+		string? initialMetricTag = null,
 		DateTime? slicerStartUtc = null, DateTime? slicerEndUtc = null,
-		int slicerDaysBack = 30)
+		int? slicerDaysBack = null)
 	{
 		InitializeComponent();
 
+		var settings = AppSettingsService.Load();
+		var metricTag = initialMetricTag ?? settings.QueryHistoryDefaultMetric;
+		var daysBack = slicerDaysBack ?? settings.QueryStoreSlicerDays;
+
 		var control = new QueryStoreHistoryControl(
 			connectionString, queryHash, queryText, database,
-			initialMetricTag, slicerStartUtc, slicerEndUtc, slicerDaysBack);
+			metricTag, slicerStartUtc, slicerEndUtc, daysBack);
 		control.ShowCloseButton(true);
 		Content = control;
 		HistoryControlInstance = control;
diff --git a/src/PlanViewer.App/Dialogs/SettingsWindow.axaml b/src/PlanViewer.App/Dialogs/SettingsWindow.axaml
new file mode 100644
index 0000000..1dc5558
--- /dev/null
+++ b/src/PlanViewer.App/Dialogs/SettingsWindow.axaml
@@ -0,0 +1,72 @@
+<Window xmlns="https://github.com/avaloniaui"
+		xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+		x:Class="PlanViewer.App.Dialogs.SettingsWindow"
+		Title="Settings"
+		Width="820" Height="620"
+		MinWidth="700" MinHeight="480"
+		WindowStartupLocation="CenterOwner"
+		Icon="avares://PlanViewer.App/EDD.ico"
+		Background="{DynamicResource BackgroundBrush}">
+
+	<Window.Styles>
+		<Style Selector="ToggleSwitch">
+			<Setter Property="OnContent" Value=""/>
+			<Setter Property="OffContent" Value=""/>
+			<Setter Property="MinWidth" Value="0"/>
+			<Setter Property="MinHeight" Value="0"/>
+			<Setter Property="Padding" Value="0"/>
+			<Setter Property="Margin" Value="0"/>
+			<Setter Property="VerticalAlignment" Value="Center"/>
+			<Setter Property="RenderTransformOrigin" Value="0%,50%"/>
+			<Setter Property="RenderTransform" Value="scale(0.75)"/>
+		</Style>
+		<Style Selector="ToggleSwitch:checked /template/ Border#SwitchKnobBounds">
+			<Setter Property="Background" Value="{DynamicResource AccentBrush}"/>
+			<Setter Property="BorderBrush" Value="{DynamicResource AccentBrush}"/>
+		</Style>
+		<Style Selector="ToggleSwitch:checked /template/ Border#OuterBorder">
+			<Setter Property="BorderBrush" Value="{DynamicResource AccentBrush}"/>
+		</Style>
+	</Window.Styles>
+
+	<DockPanel>
+		<!-- Bottom button bar -->
+		<Border DockPanel.Dock="Bottom" Background="{DynamicResource BackgroundDarkBrush}"
+				Padding="12,8">
+			<StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8">
+					<Button x:Name="ResetAllButton" Content="Reset All to Defaults" Click="ResetAll_Click"
+							Height="32" Padding="16,0" FontSize="12"
+							Theme="{StaticResource AppButton}"/>
+					<Button x:Name="ResetButton" Content="Reset Section" Click="Reset_Click"
+							Height="32" Padding="16,0" FontSize="12"
+							Theme="{StaticResource AppButton}"/>
+				<Button x:Name="SaveButton" Content="Save" Click="Save_Click"
+						Height="32" Padding="16,0" FontSize="12"
+						Theme="{StaticResource AppButton}"/>
+				<Button x:Name="CancelButton" Content="Cancel" Click="Cancel_Click"
+						Height="32" Padding="16,0" FontSize="12"
+						Theme="{StaticResource AppButton}"/>
+			</StackPanel>
+		</Border>
+
+		<!-- Main content: sidebar + detail -->
+		<Grid ColumnDefinitions="180,*">
+			<!-- Sidebar -->
+			<Border Grid.Column="0" Background="{DynamicResource BackgroundDarkBrush}"
+					Padding="0,8">
+				<ListBox x:Name="SectionList" SelectionChanged="SectionList_SelectionChanged"
+						 Background="Transparent"
+						 Foreground="{DynamicResource ForegroundBrush}">
+					<ListBoxItem Content="Query Store" IsSelected="True"/>
+					<ListBoxItem Content="Query History"/>
+					<ListBoxItem Content="Script Options"/>
+				</ListBox>
+			</Border>
+
+			<!-- Detail panel -->
+			<ScrollViewer Grid.Column="1" Padding="20,12">
+				<ContentControl x:Name="DetailPanel"/>
+			</ScrollViewer>
+		</Grid>
+	</DockPanel>
+</Window>
diff --git a/src/PlanViewer.App/Dialogs/SettingsWindow.axaml.cs b/src/PlanViewer.App/Dialogs/SettingsWindow.axaml.cs
new file mode 100644
index 0000000..36eefa4
--- /dev/null
+++ b/src/PlanViewer.App/Dialogs/SettingsWindow.axaml.cs
@@ -0,0 +1,732 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.ComponentModel;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Controls.Shapes;
+using Avalonia.Controls.Templates;
+using Avalonia.Data;
+using Avalonia.Interactivity;
+using Avalonia.Layout;
+using Avalonia.Media;
+using PlanViewer.App.Services;
+using PlanViewer.Core.Services;
+
+namespace PlanViewer.App.Dialogs;
+
+internal partial class SettingsWindow : Window
+{
+	private AppSettings _settings;
+	private bool _isDirty;
+
+	// QueryStore controls
+	private NumericUpDown? _slicerDaysBox;
+	private ComboBox? _defaultMetricBox;
+	private NumericUpDown? _topLimitBox;
+	private ComboBox? _defaultTimeRangeBox;
+	private ComboBox? _defaultTimeDisplayBox;
+	private ComboBox? _defaultGroupByBox;
+
+	// Multi QS Overview controls
+	private NumericUpDown? _topDbCountBox;
+	private readonly List<TextBox> _colorTextBoxes = new();
+	private readonly List<Rectangle> _colorPreviews = new();
+	private StackPanel? _colorListPanel;
+
+	// Query History controls
+	private ComboBox? _historyMetricBox;
+	private NumericUpDown? _historyMaxPlansBox;
+
+	// Script Options (Format) controls
+	private readonly ObservableCollection<FormatOptionRow> _formatRows = new();
+	private DataGrid? _formatGrid;
+
+	internal event Action<AppSettings>? SettingsSaved;
+
+	public SettingsWindow()
+	{
+		_settings = AppSettingsService.Load();
+		InitializeComponent();
+		ShowSection(0);
+	}
+
+	internal SettingsWindow(AppSettings settings)
+	{
+		_settings = settings.Clone();
+		InitializeComponent();
+		ShowSection(0);
+	}
+
+	private void SectionList_SelectionChanged(object? sender, SelectionChangedEventArgs e)
+	{
+		if (SectionList.SelectedIndex >= 0)
+			ShowSection(SectionList.SelectedIndex);
+	}
+
+	private void ShowSection(int index)
+	{
+		DetailPanel.Content = index switch
+		{
+			0 => BuildQueryStoreSection(),
+			1 => BuildQueryHistorySection(),
+			2 => BuildScriptOptionsSection(),
+			_ => null
+		};
+	}
+
+	// ── Query Store Section ──────────────────────────────────────────
+
+	private static readonly (string Content, string Tag)[] MetricOptions =
+	{
+		("Total CPU", "cpu"), ("Avg CPU", "avg-cpu"),
+		("Total Duration", "duration"), ("Avg Duration", "avg-duration"),
+		("Total Reads", "reads"), ("Avg Reads", "avg-reads"),
+		("Total Writes", "writes"), ("Avg Writes", "avg-writes"),
+		("Total Physical Reads", "physical-reads"), ("Avg Physical Reads", "avg-physical-reads"),
+		("Total Memory", "memory"), ("Avg Memory", "avg-memory"),
+		("Executions", "executions"),
+	};
+
+	private static readonly (string Content, string Tag)[] TimeRangeOptions =
+	{
+		("3 hours", "3"), ("24 hours", "24"), ("48 hours", "48"),
+		("7 days", "168"), ("30 days", "720"),
+	};
+
+	private static readonly (string Content, string Tag)[] TimeDisplayOptions =
+	{
+		("Local", "Local"), ("UTC", "Utc"), ("Server", "Server"),
+	};
+
+	private static readonly (string Content, string Tag)[] GroupByOptions =
+	{
+		("None", "None"), ("Query Hash", "QueryHash"), ("Module", "Module"),
+	};
+
+	private Control BuildQueryStoreSection()
+	{
+		var panel = new StackPanel { Spacing = 16 };
+
+		// Chapter 1: Query Store
+		panel.Children.Add(CreateChapterHeader("Query Store"));
+
+		_slicerDaysBox = CreateNumericUpDown(_settings.QueryStoreSlicerDays, 1, 365);
+		_slicerDaysBox.ValueChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Default history length (days)", _slicerDaysBox));
+
+		_defaultMetricBox = CreateTagComboBox(MetricOptions, _settings.QueryStoreDefaultMetric);
+		_defaultMetricBox.SelectionChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Default metric for top", _defaultMetricBox));
+
+		_topLimitBox = CreateNumericUpDown(_settings.QueryStoreTopLimit, 1, 200);
+		_topLimitBox.ValueChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Top elements limit", _topLimitBox));
+
+		_defaultTimeRangeBox = CreateTagComboBox(TimeRangeOptions, _settings.QueryStoreDefaultTimeRange);
+		_defaultTimeRangeBox.SelectionChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Default time range", _defaultTimeRangeBox));
+
+		_defaultTimeDisplayBox = CreateTagComboBox(TimeDisplayOptions, _settings.QueryStoreDefaultTimeDisplay);
+		_defaultTimeDisplayBox.SelectionChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Default time display", _defaultTimeDisplayBox));
+
+		_defaultGroupByBox = CreateTagComboBox(GroupByOptions, _settings.QueryStoreDefaultGroupBy);
+		_defaultGroupByBox.SelectionChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Default group by", _defaultGroupByBox));
+
+		// Chapter 2: Multi QS Overview
+		panel.Children.Add(CreateChapterHeader("Multi QS Overview"));
+
+		_topDbCountBox = CreateNumericUpDown(_settings.MultiQsTopDbCount, 2, 20);
+		_topDbCountBox.ValueChanged += (_, e) =>
+		{
+			_isDirty = true;
+			RebuildColorList();
+		};
+		panel.Children.Add(CreateRow("Number of top databases", _topDbCountBox));
+
+		_colorListPanel = new StackPanel { Spacing = 4 };
+		RebuildColorList();
+		panel.Children.Add(CreateRow("Top database colors", _colorListPanel));
+
+		return panel;
+	}
+
+	private void RebuildColorList()
+	{
+		if (_colorListPanel == null) return;
+		_colorListPanel.Children.Clear();
+		_colorTextBoxes.Clear();
+		_colorPreviews.Clear();
+
+		var count = (int)(_topDbCountBox?.Value ?? _settings.MultiQsTopDbCount);
+		var colors = _settings.MultiQsTopDbColors;
+
+		for (int i = 0; i < count; i++)
+		{
+			var hex = i < colors.Count ? colors[i] : AppSettingsService.DefaultTopDbColors[i % AppSettingsService.DefaultTopDbColors.Count];
+			var preview = new Rectangle
+			{
+				Width = 24, Height = 24,
+				Fill = TryParseBrush(hex),
+				RadiusX = 3, RadiusY = 3,
+				Margin = new Thickness(0, 0, 6, 0)
+			};
+			var textBox = new TextBox
+			{
+				Text = hex, Width = 100, Height = 28, FontSize = 12,
+				Foreground = (IBrush?)this.FindResource("ForegroundBrush") ?? Brushes.White
+			};
+			var index = i;
+			textBox.TextChanged += (_, _) =>
+			{
+				_isDirty = true;
+				if (index < _colorPreviews.Count)
+					_colorPreviews[index].Fill = TryParseBrush(textBox.Text ?? "");
+			};
+
+			_colorTextBoxes.Add(textBox);
+			_colorPreviews.Add(preview);
+
+			var row = new StackPanel
+			{
+				Orientation = Orientation.Horizontal,
+				Spacing = 4,
+				Children =
+				{
+					new TextBlock
+					{
+						Text = $"#{i + 1}",
+						Width = 28,
+						VerticalAlignment = VerticalAlignment.Center,
+						Foreground = (IBrush?)this.FindResource("ForegroundBrush") ?? Brushes.White,
+						FontSize = 12
+					},
+					preview,
+					textBox
+				}
+			};
+			_colorListPanel.Children.Add(row);
+		}
+	}
+
+	private static SolidColorBrush TryParseBrush(string hex)
+	{
+		try
+		{
+			return new SolidColorBrush(Color.Parse(hex));
+		}
+		catch
+		{
+			return new SolidColorBrush(Colors.Gray);
+		}
+	}
+
+	// ── Query History Section ────────────────────────────────────────
+
+	private static readonly (string Content, string Tag)[] HistoryMetricOptions =
+	{
+		("Avg CPU (ms)", "AvgCpuMs"), ("Avg Duration (ms)", "AvgDurationMs"),
+		("Avg Logical Reads", "AvgLogicalReads"), ("Avg Logical Writes", "AvgLogicalWrites"),
+		("Avg Physical Reads", "AvgPhysicalReads"), ("Avg Memory (MB)", "AvgMemoryMb"),
+		("Avg Rows", "AvgRowcount"),
+		("Total CPU (ms)", "TotalCpuMs"), ("Total Duration (ms)", "TotalDurationMs"),
+		("Total Reads", "TotalLogicalReads"), ("Total Writes", "TotalLogicalWrites"),
+		("Total Physical Reads", "TotalPhysicalReads"), ("Total Memory (MB)", "TotalMemoryMb"),
+		("Executions", "CountExecutions"),
+	};
+
+	private Control BuildQueryHistorySection()
+	{
+		var panel = new StackPanel { Spacing = 16 };
+		panel.Children.Add(CreateChapterHeader("Query History"));
+
+		_historyMetricBox = CreateTagComboBox(HistoryMetricOptions, _settings.QueryHistoryDefaultMetric);
+		_historyMetricBox.SelectionChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Default chart metric", _historyMetricBox));
+
+		_historyMaxPlansBox = CreateNumericUpDown(_settings.QueryHistoryMaxPlans, 1, 100);
+		_historyMaxPlansBox.ValueChanged += (_, _) => _isDirty = true;
+		panel.Children.Add(CreateRow("Max plans fetched per query", _historyMaxPlansBox));
+
+		return panel;
+	}
+
+	// ── Script Options Section ───────────────────────────────────────
+
+	private static readonly string[] FormatPropertyOrder =
+	[
+		"KeywordCasing", "SqlVersion", "IndentationSize",
+		"AlignClauseBodies", "AlignColumnDefinitionFields", "AlignSetClauseItem",
+		"AsKeywordOnOwnLine", "IncludeSemicolons",
+		"IndentSetClause", "IndentViewBody",
+		"MultilineInsertSourcesList", "MultilineInsertTargetsList",
+		"MultilineSelectElementsList", "MultilineSetClauseItems",
+		"MultilineViewColumnsList", "MultilineWherePredicatesList",
+		"NewLineBeforeCloseParenthesisInMultilineList",
+		"NewLineBeforeFromClause", "NewLineBeforeGroupByClause",
+		"NewLineBeforeHavingClause", "NewLineBeforeJoinClause",
+		"NewLineBeforeOffsetClause", "NewLineBeforeOpenParenthesisInMultilineList",
+		"NewLineBeforeOrderByClause", "NewLineBeforeOutputClause",
+		"NewLineBeforeWhereClause", "NewLineBeforeWindowClause",
+	];
+
+	private static readonly Dictionary<string, string[]> FormatChoiceOptionsMap = new()
+	{
+		["KeywordCasing"] = ["Uppercase", "Lowercase", "PascalCase"],
+		["SqlVersion"] = ["80", "90", "100", "110", "120", "130", "140", "150", "160", "170"],
+	};
+
+	private Control BuildScriptOptionsSection()
+	{
+		var panel = new StackPanel { Spacing = 16 };
+		panel.Children.Add(CreateChapterHeader("Format Options"));
+
+		var current = _settings.FormatOptions ?? new SqlFormatSettings();
+		var defaults = new SqlFormatSettings();
+		_formatRows.Clear();
+
+		var props = typeof(SqlFormatSettings).GetProperties(BindingFlags.Public | BindingFlags.Instance)
+			.ToDictionary(p => p.Name);
+
+		foreach (var name in FormatPropertyOrder)
+		{
+			if (!props.TryGetValue(name, out var prop)) continue;
+
+			var currentVal = prop.GetValue(current);
+			var defaultVal = prop.GetValue(defaults);
+			var isBool = prop.PropertyType == typeof(bool);
+			FormatChoiceOptionsMap.TryGetValue(prop.Name, out var choiceOptions);
+
+			var row = new FormatOptionRow
+			{
+				Name = SplitPascalCase(prop.Name),
+				CurrentValue = currentVal?.ToString() ?? "",
+				DefaultValue = defaultVal?.ToString() ?? "",
+				IsBool = isBool,
+				BoolValue = isBool && currentVal is true,
+				DefaultBoolValue = isBool && defaultVal is true,
+				ChoiceOptions = choiceOptions,
+				PropertyInfo = prop
+			};
+			row.PropertyChanged += (_, _) => _isDirty = true;
+			_formatRows.Add(row);
+		}
+
+		_formatGrid = new DataGrid
+		{
+			ItemsSource = _formatRows,
+			AutoGenerateColumns = false,
+			CanUserReorderColumns = false,
+			CanUserResizeColumns = true,
+			CanUserSortColumns = false,
+			HeadersVisibility = DataGridHeadersVisibility.Column,
+			GridLinesVisibility = DataGridGridLinesVisibility.Horizontal,
+			IsReadOnly = false,
+			MinHeight = 400,
+			FontSize = 13,
+		};
+
+		_formatGrid.Columns.Add(new DataGridTextColumn
+		{
+			Header = "Setting",
+			Binding = new Binding("Name"),
+			Width = new DataGridLength(2, DataGridLengthUnitType.Star),
+			IsReadOnly = true
+		});
+
+		// Value column: ToggleSwitch for bools, ComboBox for choices, TextBox for text
+		var valueColumn = new DataGridTemplateColumn
+		{
+			Header = "Value",
+			Width = new DataGridLength(1, DataGridLengthUnitType.Star),
+		};
+		valueColumn.CellTemplate = new FuncDataTemplate<FormatOptionRow>((row, _) =>
+		{
+			if (row == null) return new Panel();
+			var container = new Panel();
+
+			if (row.IsBool)
+			{
+				var toggle = new ToggleSwitch
+				{
+					[!ToggleSwitch.IsCheckedProperty] = new Binding("BoolValue"),
+					Margin = new Thickness(4, 0),
+					VerticalAlignment = VerticalAlignment.Center,
+				};
+				container.Children.Add(toggle);
+			}
+			else if (row.IsChoice)
+			{
+				var combo = new ComboBox
+				{
+					ItemsSource = row.ChoiceOptions,
+					[!ComboBox.SelectedItemProperty] = new Binding("CurrentValue"),
+					VerticalAlignment = VerticalAlignment.Center,
+					MinHeight = 0, Height = 26, FontSize = 12,
+					Margin = new Thickness(4, 0),
+				};
+				container.Children.Add(combo);
+			}
+			else
+			{
+				var tb = new TextBox
+				{
+					[!TextBox.TextProperty] = new Binding("CurrentValue"),
+					VerticalAlignment = VerticalAlignment.Center,
+					Margin = new Thickness(4, 0),
+				};
+				container.Children.Add(tb);
+			}
+
+			return container;
+		}, supportsRecycling: false);
+		_formatGrid.Columns.Add(valueColumn);
+
+		// Default column: disabled ToggleSwitch for bools, TextBlock for others
+		var defaultColumn = new DataGridTemplateColumn
+		{
+			Header = "Default",
+			Width = new DataGridLength(1, DataGridLengthUnitType.Star),
+			IsReadOnly = true,
+		};
+		defaultColumn.CellTemplate = new FuncDataTemplate<FormatOptionRow>((row, _) =>
+		{
+			if (row == null) return new Panel();
+			var container = new Panel();
+
+			if (row.IsBool)
+			{
+				var toggle = new ToggleSwitch
+				{
+					IsChecked = row.DefaultBoolValue,
+					IsEnabled = false,
+					Margin = new Thickness(4, 0),
+					VerticalAlignment = VerticalAlignment.Center,
+				};
+				container.Children.Add(toggle);
+			}
+			else
+			{
+				container.Children.Add(new TextBlock
+				{
+					Text = row.DefaultValue,
+					VerticalAlignment = VerticalAlignment.Center,
+					Margin = new Thickness(8, 0),
+				});
+			}
+
+			return container;
+		}, supportsRecycling: false);
+		_formatGrid.Columns.Add(defaultColumn);
+
+		panel.Children.Add(_formatGrid);
+
+		var revertBtn = new Button
+		{
+			Content = "Revert Format to Defaults",
+			Height = 28, Padding = new Thickness(12, 0),
+			FontSize = 12,
+			Theme = (Avalonia.Styling.ControlTheme?)this.FindResource("AppButton")
+		};
+		revertBtn.Click += (_, _) =>
+		{
+			foreach (var row in _formatRows)
+			{
+				row.CurrentValue = row.DefaultValue;
+				if (row.IsBool)
+					row.BoolValue = row.DefaultBoolValue;
+			}
+		};
+		panel.Children.Add(revertBtn);
+
+		return panel;
+	}
+
+	private static string SplitPascalCase(string name)
+	{
+		var sb = new StringBuilder(name.Length + 8);
+		for (int i = 0; i < name.Length; i++)
+		{
+			var c = name[i];
+			if (i > 0 && char.IsUpper(c) && !char.IsUpper(name[i - 1]))
+				sb.Append(' ');
+			sb.Append(c);
+		}
+		return sb.ToString();
+	}
+
+	// ── Helpers ──────────────────────────────────────────────────────
+
+	private static readonly SolidColorBrush ChapterHeaderBg = new(Color.Parse("#2A2D35"));
+	private static readonly SolidColorBrush ChapterHeaderFg = new(Color.Parse("#4FC3F7"));
+
+	private static Border CreateChapterHeader(string text) => new()
+	{
+		Background = ChapterHeaderBg,
+		CornerRadius = new CornerRadius(4),
+		Padding = new Thickness(12, 6),
+		Margin = new Thickness(0, 8, 0, 2),
+		Child = new TextBlock
+		{
+			Text = text,
+			FontSize = 15,
+			FontWeight = FontWeight.SemiBold,
+			Foreground = ChapterHeaderFg,
+		}
+	};
+
+	private static StackPanel CreateRow(string label, Control control)
+	{
+		return new StackPanel
+		{
+			Spacing = 4,
+			Children =
+			{
+				new TextBlock { Text = label, FontSize = 13 },
+				control
+			}
+		};
+	}
+
+	private static ComboBox CreateTagComboBox((string Content, string Tag)[] options, string selectedTag)
+	{
+		var box = new ComboBox { Width = 200, Height = 32, FontSize = 13 };
+		int selectedIndex = 0;
+		for (int i = 0; i < options.Length; i++)
+		{
+			box.Items.Add(new ComboBoxItem { Content = options[i].Content, Tag = options[i].Tag });
+			if (options[i].Tag == selectedTag)
+				selectedIndex = i;
+		}
+		box.SelectedIndex = selectedIndex;
+		return box;
+	}
+
+	private static NumericUpDown CreateNumericUpDown(int value, int min, int max) => new()
+	{
+		Value = value,
+		Minimum = min, Maximum = max, FormatString = "0",
+		Width = 120, Height = 32, FontSize = 13,
+		HorizontalAlignment = HorizontalAlignment.Left,
+		HorizontalContentAlignment = HorizontalAlignment.Left,
+		TextAlignment = TextAlignment.Left,
+	};
+
+	private static string GetComboTag(ComboBox? box) =>
+		(box?.SelectedItem as ComboBoxItem)?.Tag?.ToString() ?? "";
+
+	// ── Button handlers ──────────────────────────────────────────────
+
+	private void Save_Click(object? sender, RoutedEventArgs e)
+	{
+		// Read QueryStore settings
+		_settings.QueryStoreSlicerDays = (int)(_slicerDaysBox?.Value ?? 30);
+		_settings.QueryStoreDefaultMetric = GetComboTag(_defaultMetricBox);
+		_settings.QueryStoreTopLimit = (int)(_topLimitBox?.Value ?? 25);
+		_settings.QueryStoreDefaultTimeRange = GetComboTag(_defaultTimeRangeBox);
+		_settings.QueryStoreDefaultTimeDisplay = GetComboTag(_defaultTimeDisplayBox);
+		_settings.QueryStoreDefaultGroupBy = GetComboTag(_defaultGroupByBox);
+
+		// Read Multi QS Overview settings
+		_settings.MultiQsTopDbCount = (int)(_topDbCountBox?.Value ?? 5);
+
+		// Validate hex color inputs before saving
+		var hasInvalidColor = false;
+		foreach (var tb in _colorTextBoxes)
+		{
+			try
+			{
+				Color.Parse(tb.Text ?? "");
+				tb.BorderBrush = null; // reset to default
+			}
+			catch
+			{
+				tb.BorderBrush = Brushes.Red;
+				hasInvalidColor = true;
+			}
+		}
+		if (hasInvalidColor)
+			return;
+
+		_settings.MultiQsTopDbColors = _colorTextBoxes.Select(tb => tb.Text ?? "#555555").ToList();
+
+		// Read Query History settings
+		_settings.QueryHistoryDefaultMetric = GetComboTag(_historyMetricBox);
+		_settings.QueryHistoryMaxPlans = (int)(_historyMaxPlansBox?.Value ?? 10);
+
+		// Read Format Options
+		if (_formatRows.Count > 0)
+		{
+			var fmt = new SqlFormatSettings();
+			foreach (var row in _formatRows)
+			{
+				try
+				{
+					var prop = row.PropertyInfo;
+					object? value;
+					if (prop.PropertyType == typeof(bool))
+						value = row.BoolValue;
+					else if (prop.PropertyType == typeof(int))
+					{
+						if (!int.TryParse(row.CurrentValue, out var intVal)) continue;
+						value = intVal;
+					}
+					else
+						value = row.CurrentValue;
+					prop.SetValue(fmt, value);
+				}
+				catch { /* skip bad values */ }
+			}
+			_settings.FormatOptions = fmt;
+		}
+
+		// Apply live settings
+		if (Enum.TryParse<TimeDisplayMode>(_settings.QueryStoreDefaultTimeDisplay, true, out var tdm))
+			TimeDisplayHelper.Current = tdm;
+
+		AppSettingsService.Save(_settings);
+		_isDirty = false;
+		SettingsSaved?.Invoke(_settings);
+		Close();
+	}
+
+	private void Cancel_Click(object? sender, RoutedEventArgs e)
+	{
+		TryClose();
+	}
+
+	private void Reset_Click(object? sender, RoutedEventArgs e)
+	{
+		var fresh = new AppSettings();
+		var section = SectionList.SelectedIndex;
+
+		switch (section)
+		{
+			case 0: // Query Store
+				_settings.QueryStoreSlicerDays = fresh.QueryStoreSlicerDays;
+				_settings.QueryStoreDefaultMetric = fresh.QueryStoreDefaultMetric;
+				_settings.QueryStoreTopLimit = fresh.QueryStoreTopLimit;
+				_settings.QueryStoreDefaultTimeRange = fresh.QueryStoreDefaultTimeRange;
+				_settings.QueryStoreDefaultTimeDisplay = fresh.QueryStoreDefaultTimeDisplay;
+				_settings.QueryStoreDefaultGroupBy = fresh.QueryStoreDefaultGroupBy;
+				_settings.MultiQsTopDbCount = fresh.MultiQsTopDbCount;
+				_settings.MultiQsTopDbColors = [.. AppSettingsService.DefaultTopDbColors];
+				break;
+			case 1: // Query History
+				_settings.QueryHistoryDefaultMetric = fresh.QueryHistoryDefaultMetric;
+				_settings.QueryHistoryMaxPlans = fresh.QueryHistoryMaxPlans;
+				break;
+			case 2: // Script Options
+				_settings.FormatOptions = new SqlFormatSettings();
+				break;
+		}
+
+		_isDirty = true;
+		ShowSection(section);
+	}
+
+	private void ResetAll_Click(object? sender, RoutedEventArgs e)
+	{
+		var fresh = new AppSettings
+		{
+			RecentPlans = _settings.RecentPlans,
+			OpenPlans = _settings.OpenPlans,
+			AccuracyRatioDivergenceLimit = _settings.AccuracyRatioDivergenceLimit
+		};
+		_settings = fresh;
+		_isDirty = true;
+		ShowSection(SectionList.SelectedIndex);
+	}
+
+	protected override void OnClosing(WindowClosingEventArgs e)
+	{
+		if (_isDirty)
+		{
+			e.Cancel = true;
+			TryClose();
+			return;
+		}
+		base.OnClosing(e);
+	}
+
+	private async void TryClose()
+	{
+		if (!_isDirty)
+		{
+			_isDirty = false;
+			Close();
+			return;
+		}
+
+		var result = await ShowDiscardDialog();
+		if (result)
+		{
+			_isDirty = false;
+			Close();
+		}
+	}
+
+	private async Task<bool> ShowDiscardDialog()
+	{
+		var tcs = new TaskCompletionSource<bool>();
+
+		var dialog = new Window
+		{
+			Title = "Unsaved Changes",
+			Width = 360, Height = 160,
+			MinWidth = 360, MinHeight = 160,
+			WindowStartupLocation = WindowStartupLocation.CenterOwner,
+			Background = (IBrush)this.FindResource("BackgroundBrush")!,
+			Foreground = (IBrush)this.FindResource("ForegroundBrush")!,
+			Content = new StackPanel
+			{
+				Margin = new Thickness(20),
+				Children =
+				{
+					new TextBlock
+					{
+						Text = "You have unsaved changes. Discard them?",
+						FontSize = 13, TextWrapping = TextWrapping.Wrap,
+						Margin = new Thickness(0, 0, 0, 16)
+					}
+				}
+			}
+		};
+
+		var discardBtn = new Button
+		{
+			Content = "Discard", Height = 32, Width = 90,
+			Padding = new Thickness(16, 0), FontSize = 12,
+			HorizontalContentAlignment = HorizontalAlignment.Center,
+			VerticalContentAlignment = VerticalAlignment.Center,
+			Theme = (Avalonia.Styling.ControlTheme?)this.FindResource("AppButton")
+		};
+		var cancelBtn = new Button
+		{
+			Content = "Cancel", Height = 32, Width = 90,
+			Padding = new Thickness(16, 0), FontSize = 12,
+			Margin = new Thickness(8, 0, 0, 0),
+			HorizontalContentAlignment = HorizontalAlignment.Center,
+			VerticalContentAlignment = VerticalAlignment.Center,
+			Theme = (Avalonia.Styling.ControlTheme?)this.FindResource("AppButton")
+		};
+
+		var buttonPanel = new StackPanel { Orientation = Orientation.Horizontal, HorizontalAlignment = HorizontalAlignment.Right };
+		buttonPanel.Children.Add(discardBtn);
+		buttonPanel.Children.Add(cancelBtn);
+		((StackPanel)dialog.Content!).Children.Add(buttonPanel);
+
+		discardBtn.Click += (_, _) => { tcs.TrySetResult(true); dialog.Close(); };
+		cancelBtn.Click += (_, _) => { tcs.TrySetResult(false); dialog.Close(); };
+		dialog.Closing += (_, _) => tcs.TrySetResult(false);
+
+		await dialog.ShowDialog(this);
+		return await tcs.Task;
+	}
+}
diff --git a/src/PlanViewer.App/MainWindow.axaml b/src/PlanViewer.App/MainWindow.axaml
index 166a9a5..19e1603 100644
--- a/src/PlanViewer.App/MainWindow.axaml
+++ b/src/PlanViewer.App/MainWindow.axaml
@@ -26,6 +26,7 @@
                 <MenuItem Header="E_xit" Click="Exit_Click"
                           InputGesture="Alt+F4"/>
             </MenuItem>
+            <MenuItem Header="_Settings" Click="Settings_Click"/>
             <MenuItem Header="_Help">
                 <MenuItem Header="_About Performance Studio" Click="About_Click"/>
                 <Separator/>
diff --git a/src/PlanViewer.App/MainWindow.axaml.cs b/src/PlanViewer.App/MainWindow.axaml.cs
index 9d0638c..f162940 100644
--- a/src/PlanViewer.App/MainWindow.axaml.cs
+++ b/src/PlanViewer.App/MainWindow.axaml.cs
@@ -17,6 +17,7 @@
 using Avalonia.Platform.Storage;
 using Avalonia.Threading;
 using PlanViewer.App.Controls;
+using PlanViewer.App.Dialogs;
 using PlanViewer.App.Services;
 using PlanViewer.Core.Interfaces;
 using PlanViewer.Core.Models;
@@ -37,6 +38,7 @@ public partial class MainWindow : Window
     private CancellationTokenSource? _mcpCts;
     private int _queryCounter;
     private AppSettings _appSettings;
+    private SettingsWindow? _settingsWindow;
 
     /// <summary>
     /// Set to true when the main window is closing. Detached windows check this
@@ -50,6 +52,10 @@ public MainWindow()
         _connectionStore = new ConnectionStore();
         _appSettings = AppSettingsService.Load();
 
+        // Apply user preferences on startup
+        if (Enum.TryParse<TimeDisplayMode>(_appSettings.QueryStoreDefaultTimeDisplay, true, out var tdm))
+            TimeDisplayHelper.Current = tdm;
+
         // Listen for file paths from other instances (e.g. SSMS extension)
         StartPipeServer();
 
@@ -237,6 +243,23 @@ private void Exit_Click(object? sender, RoutedEventArgs e)
         Close();
     }
 
+    private void Settings_Click(object? sender, RoutedEventArgs e)
+    {
+        if (_settingsWindow != null)
+        {
+            _settingsWindow.Activate();
+            return;
+        }
+
+        _settingsWindow = new SettingsWindow(_appSettings);
+        _settingsWindow.SettingsSaved += settings =>
+        {
+            _appSettings = settings;
+        };
+        _settingsWindow.Closed += (_, _) => _settingsWindow = null;
+        _settingsWindow.Show(this);
+    }
+
     private void About_Click(object? sender, RoutedEventArgs e)
     {
         var about = new AboutWindow();
diff --git a/src/PlanViewer.App/Services/AppSettingsService.cs b/src/PlanViewer.App/Services/AppSettingsService.cs
index add43df..6c730cb 100644
--- a/src/PlanViewer.App/Services/AppSettingsService.cs
+++ b/src/PlanViewer.App/Services/AppSettingsService.cs
@@ -1,7 +1,7 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
-using System.Linq;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
@@ -15,6 +15,9 @@ internal sealed class AppSettingsService
     private const int MaxRecentPlans = 10;
     private static readonly string SettingsDir;
     private static readonly string SettingsPath;
+    private static readonly string OldFormatSettingsPath;
+
+    private static AppSettings? _cached;
 
     static AppSettingsService()
     {
@@ -22,6 +25,7 @@ static AppSettingsService()
             Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
             "PerformanceStudio");
         SettingsPath = Path.Combine(SettingsDir, "appsettings.json");
+        OldFormatSettingsPath = Path.Combine(SettingsDir, "perfstudio_format_settings.json");
     }
 
     private static readonly JsonSerializerOptions JsonOptions = new()
@@ -30,26 +34,64 @@ static AppSettingsService()
         DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
     };
 
+    /// <summary>
+    /// Options used by <see cref="AppSettings.Clone"/> — includes nulls so the roundtrip is lossless.
+    /// </summary>
+    internal static readonly JsonSerializerOptions CloneOptions = new()
+    {
+        WriteIndented = false,
+        DefaultIgnoreCondition = JsonIgnoreCondition.Never
+    };
+
     /// <summary>
     /// Loads settings from disk. Returns default settings if the file is missing or corrupt.
+    /// Migrates legacy format settings from the old standalone file if present.
     /// </summary>
+    /// <remarks>
+    /// Returns the in-process cached instance — callers must not mutate it. Use
+    /// <see cref="AppSettings.Clone"/> if you need an editable copy, or <see cref="Save"/>
+    /// to persist new state (which also refreshes the cache).
+    /// </remarks>
     public static AppSettings Load()
     {
+        if (_cached != null)
+            return _cached;
+
         try
         {
+            AppSettings settings;
             if (!File.Exists(SettingsPath))
-                return new AppSettings();
+                settings = new AppSettings();
+            else
+            {
+                var json = File.ReadAllText(SettingsPath);
+                settings = JsonSerializer.Deserialize<AppSettings>(json, JsonOptions) ?? new AppSettings();
+            }
+
+            // Migrate legacy format settings file into unified settings
+            MigrateFormatSettings(settings);
+
+            // Clamp numeric values to valid ranges
+            settings.QueryStoreSlicerDays = Math.Clamp(settings.QueryStoreSlicerDays, 1, 365);
+            settings.QueryStoreTopLimit = Math.Clamp(settings.QueryStoreTopLimit, 1, 200);
+            settings.MultiQsTopDbCount = Math.Clamp(settings.MultiQsTopDbCount, 2, 20);
+            settings.QueryHistoryMaxPlans = Math.Clamp(settings.QueryHistoryMaxPlans, 1, 100);
 
-            var json = File.ReadAllText(SettingsPath);
-            var settings = JsonSerializer.Deserialize<AppSettings>(json, JsonOptions);
-            return settings ?? new AppSettings();
+            _cached = settings;
+            return settings;
         }
-        catch
+        catch (Exception ex)
         {
+            Debug.WriteLine($"AppSettings: failed to load settings: {ex.Message}");
             return new AppSettings();
         }
     }
 
+    /// <summary>
+    /// Clears the in-process settings cache so the next <see cref="Load"/> re-reads from disk.
+    /// </summary>
+    public static void Invalidate() => _cached = null;
+
     /// <summary>
     /// Saves settings to disk. Silently ignores write failures.
     /// </summary>
@@ -60,6 +102,7 @@ public static void Save(AppSettings settings)
             Directory.CreateDirectory(SettingsDir);
             var json = JsonSerializer.Serialize(settings, JsonOptions);
             AtomicFile.WriteAllText(SettingsPath, json);
+            _cached = settings;
         }
         catch
         {
@@ -67,6 +110,40 @@ public static void Save(AppSettings settings)
         }
     }
 
+    /// <summary>
+    /// If the old perfstudio_format_settings.json exists, migrate it into AppSettings
+    /// (when FormatOptions is not yet set) and delete the old file unconditionally.
+    /// Note: this intentionally calls <see cref="Save"/> inside <see cref="Load"/> as a
+    /// one-time migration step. If Save fails, the old file remains and migration retries
+    /// on the next Load — acceptable because the window is small and self-healing.
+    /// </summary>
+    private static void MigrateFormatSettings(AppSettings settings)
+    {
+        try
+        {
+            if (!File.Exists(OldFormatSettingsPath))
+                return;
+
+            if (settings.FormatOptions == null)
+            {
+                var json = File.ReadAllText(OldFormatSettingsPath);
+                var legacy = JsonSerializer.Deserialize<SqlFormatSettings>(json, JsonOptions);
+                if (legacy != null)
+                {
+                    settings.FormatOptions = legacy;
+                    Save(settings);
+                }
+            }
+
+            // Delete the old file whether we migrated or FormatOptions was already set
+            File.Delete(OldFormatSettingsPath);
+        }
+        catch (Exception ex)
+        {
+            Debug.WriteLine($"AppSettingsService: failed to migrate format settings: {ex.Message}");
+        }
+    }
+
     /// <summary>
     /// Adds a file path to the recent plans list (most recent first).
     /// Deduplicates by full path (case-insensitive on Windows).
@@ -95,6 +172,15 @@ public static void RemoveRecentPlan(AppSettings settings, string filePath)
         settings.RecentPlans.RemoveAll(p =>
             string.Equals(p, filePath, StringComparison.OrdinalIgnoreCase));
     }
+
+    /// <summary>
+    /// Default color palette for Multi QS Overview top databases.
+    /// </summary>
+    internal static readonly List<string> DefaultTopDbColors = new()
+    {
+        "#2EAEF1", "#F2994A", "#27AE60", "#9B51E0", "#EB5757",
+        "#F2C94C", "#56CCF2", "#BB6BD9", "#E91E63", "#00BCD4",
+    };
 }
 
 /// <summary>
@@ -102,18 +188,23 @@ public static void RemoveRecentPlan(AppSettings settings, string filePath)
 /// </summary>
 internal sealed class AppSettings
 {
-    /// <summary>
-    /// Most recently opened plan file paths, newest first. Max 10.
-    /// </summary>
+    // ── App State ────────────────────────────────────────────────────
+
     [JsonPropertyName("recent_plans")]
     public List<string> RecentPlans { get; set; } = new();
 
-    /// <summary>
-    /// File paths that were open when the app last closed — restored on next launch.
-    /// </summary>
     [JsonPropertyName("open_plans")]
     public List<string> OpenPlans { get; set; } = new();
 
+    /// <summary>
+    /// Divergence limit for accuracy ratio coloring on plan links. Default 10.
+    /// Links with accuracy ratio between 1/limit and limit keep the default edge color.
+    /// </summary>
+    [JsonPropertyName("accuracy_ratio_divergence_limit")]
+    public double AccuracyRatioDivergenceLimit { get; set; } = 10;
+
+    // ── Query Store Settings ─────────────────────────────────────────
+
     /// <summary>
     /// Number of days of Query Store data to load in the time-range slicer. Default 30.
     /// </summary>
@@ -121,9 +212,80 @@ internal sealed class AppSettings
     public int QueryStoreSlicerDays { get; set; } = 30;
 
     /// <summary>
-    /// Divergence limit for accuracy ratio coloring on plan links. Default 10.
-    /// Links with accuracy ratio between 1/limit and limit keep the default edge color.
+    /// Default metric for the top queries grid. Default "cpu" (= Total CPU).
+    /// Values: cpu, avg-cpu, duration, avg-duration, reads, avg-reads,
+    /// writes, avg-writes, physical-reads, avg-physical-reads, memory, avg-memory, executions.
     /// </summary>
-    [JsonPropertyName("accuracy_ratio_divergence_limit")]
-    public double AccuracyRatioDivergenceLimit { get; set; } = 10;
+    [JsonPropertyName("query_store_default_metric")]
+    public string QueryStoreDefaultMetric { get; set; } = "cpu";
+
+    /// <summary>
+    /// Default number of top elements/groups shown in the grid. Default 25.
+    /// </summary>
+    [JsonPropertyName("query_store_top_limit")]
+    public int QueryStoreTopLimit { get; set; } = 25;
+
+    /// <summary>
+    /// Default time range quick-filter selection (hours as string).
+    /// Options: "3" (3h), "24" (24h), "48" (48h), "168" (7d), "720" (30d).
+    /// </summary>
+    [JsonPropertyName("query_store_default_time_range")]
+    public string QueryStoreDefaultTimeRange { get; set; } = "24";
+
+    /// <summary>
+    /// Default time display mode: "Local", "Utc", or "Server".
+    /// </summary>
+    [JsonPropertyName("query_store_default_time_display")]
+    public string QueryStoreDefaultTimeDisplay { get; set; } = "Local";
+
+    /// <summary>
+    /// Default group-by mode: "None", "QueryHash", or "Module".
+    /// </summary>
+    [JsonPropertyName("query_store_default_group_by")]
+    public string QueryStoreDefaultGroupBy { get; set; } = "QueryHash";
+
+    // ── Multi QS Overview Settings ───────────────────────────────────
+
+    /// <summary>
+    /// Number of top databases shown in the overview. Default 5, min 2, max 20.
+    /// </summary>
+    [JsonPropertyName("multi_qs_top_db_count")]
+    public int MultiQsTopDbCount { get; set; } = 5;
+
+    /// <summary>
+    /// Hex color codes for top databases in the overview chart.
+    /// </summary>
+    [JsonPropertyName("multi_qs_top_db_colors")]
+    public List<string> MultiQsTopDbColors { get; set; } = new(AppSettingsService.DefaultTopDbColors);
+
+    // ── Query History Settings ───────────────────────────────────────
+
+    /// <summary>
+    /// Default metric for the query history chart. Default "AvgDurationMs".
+    /// </summary>
+    [JsonPropertyName("query_history_default_metric")]
+    public string QueryHistoryDefaultMetric { get; set; } = "AvgDurationMs";
+
+    /// <summary>
+    /// Maximum number of plans fetched for a query history. Default 10, min 1, max 100.
+    /// </summary>
+    [JsonPropertyName("query_history_max_plans")]
+    public int QueryHistoryMaxPlans { get; set; } = 10;
+
+    // ── Script Options (Format) ──────────────────────────────────────
+
+    /// <summary>
+    /// SQL format options. Null means use <see cref="SqlFormatSettings"/> defaults.
+    /// </summary>
+    [JsonPropertyName("format_options")]
+    public SqlFormatSettings? FormatOptions { get; set; }
+
+    /// <summary>
+    /// Creates a deep copy via JSON roundtrip so mutations don't leak to callers.
+    /// </summary>
+    internal AppSettings Clone()
+    {
+        var json = JsonSerializer.Serialize(this, AppSettingsService.CloneOptions);
+        return JsonSerializer.Deserialize<AppSettings>(json, AppSettingsService.CloneOptions) ?? new AppSettings();
+    }
 }
diff --git a/src/PlanViewer.App/Services/SqlFormatSettingsService.cs b/src/PlanViewer.App/Services/SqlFormatSettingsService.cs
index 179e908..647fc8c 100644
--- a/src/PlanViewer.App/Services/SqlFormatSettingsService.cs
+++ b/src/PlanViewer.App/Services/SqlFormatSettingsService.cs
@@ -1,7 +1,4 @@
 using System;
-using System.Diagnostics;
-using System.IO;
-using System.Text.Json;
 using Microsoft.SqlServer.TransactSql.ScriptDom;
 
 namespace PlanViewer.App.Services;
@@ -81,56 +78,4 @@ public SqlScriptGeneratorOptions ToGeneratorOptions()
     }
 }
 
-/// <summary>
-/// Loads and saves <see cref="SqlFormatSettings"/> to a local JSON file.
-/// </summary>
-internal static class SqlFormatSettingsService
-{
-    private static readonly string SettingsDir = Path.Combine(
-        Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-        "PerformanceStudio");
-
-    private static readonly string SettingsPath = Path.Combine(SettingsDir, "perfstudio_format_settings.json");
-
-    private static readonly JsonSerializerOptions JsonOptions = new()
-    {
-        WriteIndented = true
-    };
-
-    public static SqlFormatSettings Load(out string? error)
-    {
-        error = null;
-        try
-        {
-            if (!File.Exists(SettingsPath))
-                return new SqlFormatSettings();
 
-            var json = File.ReadAllText(SettingsPath);
-            return JsonSerializer.Deserialize<SqlFormatSettings>(json, JsonOptions) ?? new SqlFormatSettings();
-        }
-        catch (Exception ex)
-        {
-            Debug.WriteLine($"SqlFormatSettings: failed to load settings: {ex.Message}");
-            error = $"Could not load format settings from:\n{SettingsPath}\n\n{ex.Message}\n\nUsing defaults. Delete or fix the file to clear this error.";
-            return new SqlFormatSettings();
-        }
-    }
-
-    public static bool Save(SqlFormatSettings settings, out string? error)
-    {
-        error = null;
-        try
-        {
-            Directory.CreateDirectory(SettingsDir);
-            var json = JsonSerializer.Serialize(settings, JsonOptions);
-            AtomicFile.WriteAllText(SettingsPath, json);
-            return true;
-        }
-        catch (Exception ex)
-        {
-            Debug.WriteLine($"SqlFormatSettings: failed to save settings: {ex.Message}");
-            error = $"Could not save format settings to:\n{SettingsPath}\n\n{ex.Message}\n\nCheck that the folder is writable and not locked by another process.";
-            return false;
-        }
-    }
-}
diff --git a/src/PlanViewer.Ssms/Properties/AssemblyInfo.cs b/src/PlanViewer.Ssms/Properties/AssemblyInfo.cs
index 50ef0a8..ca2570c 100644
--- a/src/PlanViewer.Ssms/Properties/AssemblyInfo.cs
+++ b/src/PlanViewer.Ssms/Properties/AssemblyInfo.cs
@@ -7,5 +7,5 @@
 [assembly: AssemblyProduct("Performance Studio for SSMS")]
 [assembly: AssemblyCopyright("Copyright Darling Data 2026")]
 [assembly: ComVisible(false)]
-[assembly: AssemblyVersion("1.11.2.0")]
-[assembly: AssemblyFileVersion("1.11.2.0")]
+[assembly: AssemblyVersion("1.12.0.0")]
+[assembly: AssemblyFileVersion("1.12.0.0")]
diff --git a/src/PlanViewer.Ssms/source.extension.vsixmanifest b/src/PlanViewer.Ssms/source.extension.vsixmanifest
index 7a1488a..059fd19 100644
--- a/src/PlanViewer.Ssms/source.extension.vsixmanifest
+++ b/src/PlanViewer.Ssms/source.extension.vsixmanifest
@@ -3,7 +3,7 @@
                  xmlns:d="http://schemas.microsoft.com/developer/vsx-schema-design/2011">
   <Metadata>
     <Identity Id="PlanViewer.Ssms.64F79022-9D9A-4463-A1AE-4B19426A0CB1"
-              Version="1.11.2"
+              Version="1.12.0"
               Language="en-US"
               Publisher="Darling Data" />
     <DisplayName>Performance Studio for SSMS</DisplayName>