over a 4 line i would suggest a ornate pimlodus, they do hand feed as shown on planet catfish, are closely related to the other two and top out at 12 inch!-) cichlid wise i would do firemouth, green sev and hrp convict... might even think about a cuban aswell! good luck sounds like an awesome setup.
couple of fluval f4 would be a good filter setup imo.