+1 on the large lion lair!
You could go with a P. volitans and a P. russelii, one or two of the larger scorps (Scorpaena brasiliensis is a good one), an Inimicus sp. stingfish, a squirrelfish/soldierfish, Xanthicthys sp. trigger (I like the crosshatch), a foxface/rabbitfish, marine betta...lots of possibilities.