I'd definitely say you might want to consider 'Mbunu' cichlids. Most grow between 3-5" sometimes a little bigger, and there are many colors and levels of aggression for anything from a fairly easy and docile tank to something with more fiesty fish! You can also keep more of them together since they are fairly small for cichlids. Most Mbunu are also either omnivorous or herbivorous, so its easy to combine fishes for an easy-to-maintain... and VERY colorful... cichlid setup.
I'm certainly working on setting up my own 'Mbunu' tank. Mine is going to have Labidochromis Sp., and possibly some of either Pseudotropheus Demansoni, Pseudo. Scofafli, Lamprologus Tretocephalus, and/or Melanochromis Cyaneorhabdos. I'm working on a diachromatic blue/yellow theme.