If you don't want to deal with cichlid aggression, you could go with something like a mixed group of rainbowfish. You will still get lots of chasing among themselves but they won't kill each other. Any species would be possible in this takn size and could do a pretty large group.
The peacock suggestion is a good one, although you will still have some aggression (probably less than mbuna though). But personally I wouldn't let it dissuade me.
The peacock suggestion is a good one, although you will still have some aggression (probably less than mbuna though). But personally I wouldn't let it dissuade me.