If it doesn't have to be freshwater, a titan trigger or other large trigger could be pretty sweet. Freshwater, the puffer idea is kind of cool, if not how about a male umbee?
lol that Titan trigger is a beast killer, if anyone thing Dovii mean then this Titan is freaking worse than Dovii LOL It's tear a part everything if it doesn't like...even a rock is not safe to titan trigger!A titan trigger or other large trigger.
Why no giant gourami, have you had a bad experience with them or do you just not like them? One would have been perfect, they love being on there own and are full of personality. Oscars too but one would look lost in a tank that big.
Dovii
I vote Dovii. That will be my next fish if/when I acquire a large enough tank OR a black nasty pair.