An electric Blue Jack Dempsey would go well in there. Or some ctenopomas, like african spotted leaf fish (which I have) They have a pretty sweet personality. I have a whole oddball tank and I have...
2 spiny eels
black ghost knife
royal farlowella
3 upside down cats
Electric blue jack
2 ctenopomas
school of congo tetras (an un-lame tetra)
African Buttterfly fish
like the tank thats what I'm goin for right now.
.. a while back when I first got all my bichirs and ropefish I thought I'd add in some tetra's to look nice and if they got eaten hey you know.
so I got like 20 neons (got them all dirt cheap) 2 glo light tetra's 3 silver tip and 2 serpa tetras) the first night I woke up I had about 14 neons left...
(I had over 20 feeder guppies mind you and they weren't touched!)
now.. I have 1 silver tip and one glolight left.
right now I'm planning on getting one more african butterfly and 2 leapord cten.
yeah I try to keep my tank pretty stocked on guppies plus I throw in deer heart crickets moths you name it.
the poly bichir gets the crickets before the butterfly sometimes... oddly enough