I would do the following
1 breeding pair of severums
1 female chocolate cichlid
1 male juvenile texas that I would prepare to move to another tank once he is sized up enough to play with the big boys
1 red tail shark
1 huge 8 inch festivum
1 small school of spanner and arulius barbs as targets
1 bristlenose pleco
2 panaque 40_ something pleco
1 juvenile rainbow cichlid
Mix in some serious filtration (eheim 2028, aquaclear 500, powerhead 802 with modified filter basket)
I would heat it to 82 degrees.
Throw in some onion plants, some anubius as well as a few caves and homemade driftwood.
Light it with a zoomed ultra sun.
Then sit back and enjoy the action and the tranquillity (depending on the moment).
I would do this because that is what I have right now in my 77 gallon (48LX16DX24H) and I think that it looks great.
