nearly all windows cursor packs lack certain cursors (e.g "wayland-cursor"). you can see more of these x11-exclusive cursors in breeze-cursors. from personal testing, the Inherits=... option doesn't really work as you'd expect?
anyways, an option (like --fallback-theme) to supplement missing cursors by creating symlinks (of those missing cursors) to another cursor pack could be nice. this feature also exists in ani2xcur-cli (i think), which is a win2xcur wrapper (i think, x2).