Having the ability to set a color for your macro buttons would be amazing. Maybe something similar to the system used for picking a color for Drawings? My players asked me to check into this, and I thought it was such a great idea. Having at-will abilities colored green for their macro button on the hot bar, and red for encounter, gray or black for dailies, would go a long way towards giving the players info at a glance. It could also have other uses in other game systems, like skill checks being one color while ability checks or combat checks being their own colors.