I agree that keeping greens and warmouth together in that size tank could be a problem. But if it's densely planted and has lots of hiding places, they'll probably be all right. Most other
Lepomis sunfish species would also work; avoid bluegill and redear, as they grow too big for a 55.
Madtoms will get et. I suggest you try for a snail or spotted bullhead; these are smaller than the common brown, black, and yellow bullheads (any of which would outgrow your tank, and possibly kill your sunnies), but bigger than madtoms. Both occur in northern FL. They could be hard to catch, though, and hard on your plants too.
Sculpin are not native to FL, and can be tricky to keep. A somewhat similar species that would work better for you is the fat sleeper,
Dormitator maculatus (AKA jade goby). This is a robust cousin of gobies and mudskippers.
You could keep a greater diversity of fishes, and keep your aquascaping intact, if you went with smaller, less aggressive species. The
Enneacanthus sunfishes (black-banded, blue-spotted, and banded) are small and peaceful, and could be kept with native cyprinids, killifishes, livebearers, darters, and so on.
Lots of info on FL's aquatic plants here:
http://plants.ifas.ufl.edu/node/34?categoryId=13