why not some shrimp? With a large planted tank you can have a decent size colony going. Also, you could could some longfin gold zebra danios. I don't know why, but I love the idea of them in a planted tank!
Even my smallest Black Neon will drive a shrimp nuts to its death. I will probably try some ones my Black Babaultis (I don't even know if they are Black Babaultis) gets a little bigger. So far everything is breeding in the Paludarium.
I'm not sure I want more schooling fish since I already have so many.