suggestions:
Nandus Nandus: big leaf fish, gets to 8" with a mouth big enough to eat a fish almost its own size. i own one and i have to say, although it was kinda boring at first i really like this guy now, not as much personality as a cichlid, but he is pretty cool.
(this guy is insanely skinny!!!)
any of the smaller upperjaw species of polypterus, such as delhezi, senegal, palmas polli, palmas palmas, ect. ect. they get to 12" have great personalities and i guarentee you'll be addicted to them after buying one.
(fruitbats delhezi....lol i always use fruitbat's picture when i show the del, hope he doesn't mind and too bad if he does lol)
you could also look into the needlefish, it looks like a gar (although its not) and gets to around 10".