docs: log three backlog improvements

BACKLOG.md

@@ -10,4 +10,19 @@ Issues and improvements to address eventually. Not blockers.
 
 ## Improvements
 
-*(none yet)*
+### UI: "Clear" button hover feedback in light/Dan mode
+In dark mode the "Clear" button text lightens on hover, giving visual feedback. In light
+mode and Dan mode it currently does nothing visible. Should have a matching subtle
+highlight (e.g. text darkens, underline appears, or border darkens).
+
+### Admin: user-provided IDs for units and groups
+When creating a unit or group, allow the user to optionally supply their own ID.
+- If the ID field is left empty, auto-generate it by kebab-casing the label (live
+  preview as the user types the label).
+- If the user types into the ID field, stop auto-generating and use what they typed.
+- Validate: IDs must be unique and slug-safe.
+
+### Admin: "Delete" action in the bulk actions menu
+Add a "Delete" option to the bulk action dropdown so multiple units can be deleted at
+once. Should show a confirmation dialog listing the units to be deleted before
+committing. Related to the immediate fix below (ungrouped bulk actions).