I agree with Marinemom a Dwarf Gourami would be a nice bigger fish to add and they stay near the top of the tank always in view. (mine does, have read they may hide but your other species isn't Gourami unfriendly)
Am I feeling OK or did Cory lover actually recommend something other than a Cory? Just messing with you Cory Lover. I do agree that a dwarf Gourami would look great with the other fish.