Allow editing of multiple actions at once: eg shift select a group of actions, go to action settings and set the colour for all. Allow separators in button mode.
This would help me as I have a large number of actions, grouped by the type of illustration I am working on. I usually work in button mode, so segregating by colour allows my to identify actions quickly. If I have to reset my preferences, or reload group actions, it can take nearly an hour to set this up.