Depends on aquarium size and if you believe that blue rams' natural environment is at a constant 30C.
In short, only some Corys can live at higher temperatures, and the gouramis can't. Also, dwarf gouramis can sometimes perceive blue rams as competition, so the tank needs to be quite large.
I agree that Bolivian Rams are an interesting alternative, but I would want an over 3 ft long tank for them. I recommend Apistogramma as a better alternative for a 3 fter or shorter.