ALCAR - your first suggestion is already in the "UI Wishlist" thread (and is very popular); maybe check that out and see if you'd like to add anything else.
But I have to admit I like the way the "ALT" item highlighting works now (as also mentioned in the UI list) - of course this is personal preference, but I really don't find pixel-hunting for tiny items at all fun. That said, I think a main menu option to enable/disable the highlighting could please both types of players.
