There's a nice list here of beginner fish for smaller tanks. I think five small fish would be about the limit:
Beginner Fish: Tropical Fish for Beginners in Saltwater Aquariums
I've always heard that damsels are the worst thing to put in your tank, as they'll terrorize everything. I think you either need to go for an all-damsel tank, or not get any. I've also heard that a lot get ugly as they mature.
Wrasses are jumpers, so you'll need to make sure your tank is fully covered if you decide to get one.