Although probably the most aggressive of the three, I think I would try a pair of one of the African jewell cichlids(hemichromis I assume).
The reason I would choose these is there are some lovely robust African characins to choose from for biotope correct tank mates.
Not sure if that matters to you?
There are also some nice catfish and oddballs that may be able to share the space depending on the aggression levels of the jewell.
Hardy easy to grow African plants are also easy to get hold of. Anubias and nymphia lotus spring to mind.
My second choice would be the nanos, simply because they are small and beautiful.
All would make nice residents but I've been itching to do something African for a while now.
It will be interesting to see what you come up with.