Hey milkman u could keep it simple and cheap get a spotted raphel cat or the common shovlenose cat both stay small and won't eat your really cool fish.But if u do go big money get that tig those streaming tail fins are sweet.
Get a M. Irwini or a giant armored catfish. Both look similar. Both non predators/bottom feeders and M Irwini gets 2ft, and the giant armored get 3ft. Ivan has a giant armored for sale I think 28" or so..