Well you can get anotehr type of clownfish, like the common perculas, or occelaris, or you could get skunks, saddlebacks, clarkiis, black and whites, or some of the other fancy variants and things.
Add a blenny like a midas blenny, or a sailfin blenny (just examples).
Pick two more interesting fish like pipefish, jawfish, hawkfish, eel, or puffer and your set.
Of course you'll still want to research each fish individually, but if you put some research into it its not hard..
In my 37g I have a clarkii clown, a midas blenny, a firefish, and two flame hawkfish.
Hope this helps.