Your TSN and Pacu will outgrow it, but they would outgrow most tanks wouldnt they? Your Oscar and Chocolate (I think I IDed all your fishies correctly, but lemme know if Im wrong) will be happy for years to come though.
now that you got the tank id try dressin it up a lil bit....but thats all personal preference. the only thing that seems maybe in issue is that the substrate could be a bit harsh for the ol cat. but im not a cat expert just seems like youd want something a little easier on the fish