I could...I was thinking about a Dutch aquarium, but with extra fish. It could probably support more fish than 55 neons if I add enough plants. Maybe 26 neons, a small group of corys, 5 platys, 3 Bristlenose, 4 honey gouramis, and 8 killies.
If your going to get killifish, get golden killifish. They are excellent top dwellers and have great personality. They are one of the more peaceful killifish.