I just sat up a new 40 gal bow front any fun to watch fish that I can add I would like a little more than your average damselfish thanks!!!
Go to Live Aquaria, they have a Nano Fish catagory and with any of their fish they has a suggested tank size; it's just a good reference tool.
Imo, blennies are fun to watch. Clowns live up to their name. Hawkfish can be very interesting as well.
Shrimp can fall victim to Hawkfish so keep that in mind. If I had it to do over I'd forego the shrimp to have a Hawkfish. Super interesting fish.