they definatly want a group of 6 but if you do that i would do the catfish and gourami alone again imo then watch the boiload id if dosent get too dirty slowly add some molliesi dont think so,but you might wanna look into getting more catfish,im pretty sure they like groups of 6+
thats a much better idea then you could keep everything what filter r u running?Maybe you could trade the mollies in for some guppies. Guppies are smaller and produce less waste so u could have more than 3. They prefer to be in schools too.