If you don't like fish chasing and nipping, the barbs are probably not the way to go. (I don't know about cherry barbs, as I've no experience with these fish). If they are a peaceful fish, as I've heard that they are, a keyhole cichlid may be a good choice for a centerpiece, if you're still looking to go that route. They are pretty shy and very peaceful and, in my opinion, a rather attractive fish. Here is a picture.
