I get that you're wanting a bigger fish. The comments about the red wolf fish being far more active/interactive definitely seem on track to me though. I've never kept a black or common...and one of my red wolves kind of fits that description of a "log until feeding time"...but my other red wolf fish is a VERY active little guy. He's often swimming/hunting in the tank...and when the top of the tank is opened, he's ready to eat. In fact, he's twice jumped his entire body length out of the tank to bite me while I'm feeding him!
So it is something you might consider. Granted they don't get huge, but 8-10 inches is still pretty respectable, especially when you take into account the ferocity.