This sounds like a nice setup to me, south American themed. I would just avoid the smallestdwarf species, don't want the acaras trying to eat one and choking on the dorsal spines. Most cory species should work fine however.Fish keeping is definitely more about keeping water, and I've got that bit down.
You mentioned in another post I made cory's would make good tank mates....any recommendations on which ones?
I'm thinking I might just end up doing a Cory, acara and tetra tank since my tetra are already working on spawning.