in a 37 gallon i would not add more than 1 angelfish. you might be able to get a pair, but then they will beat up on any one else. it is also not recomended to have gouramis with angelfish. They do not mix well. if you want the angelfish, pick one and then get some schooling fish that are peaceful and not fin nippers, like some sort of larger tetra. When angels get larger they could start going after and eating smaller tetras.
the pleco might be okay, i am not sure about the rams. maybe one would be okay. going with 2, especially a breeeding pair will probably produce too much aggression.
Its just that most of the fish you picked are all agressive and really cant be crammed into a smaller tank like a 37 gallon.
it will also help alot if the tank is planted. if it is heavily planted you might be able to get away with 2 angel's, but be prepared to remove one if aggression arises as they grow older and establish territories.