I love the idea of a native tank, but only have a 29 gal so it's kind of out of the question. I could put some minnows in it or something, but that's no comparison to bluegill or catfish.
Natives are not out of the question for anyone
There are several species that stay small enough to keep full life in a 29. The Orange Spotted sunfish, Obesus, Black Banded Sunfish, all stay quite small. Then there are the Darters, Very interesting and colorful (See BT Darters website) The hummingbirds of the Native Fish World.