1: Ability to easily drag and position the categories of brushes instead of just move up or down one spot. If you have a lot of categories this takes forever to order them how you want.
2: Add ability to change new brush categories placement at top of list instead of just at bottom.
3: Would be nice to move select brush categories out of brushes and place into one of the custom menu's instead of a link to that category.
This way I can close the Brushes and save some space by only working with the ones I want and hide the rest away until I need them.
4: Also ability to add more custom spaces instead of the three available and be able to rename them from Custom 1, 2, 3 to something more memorable.