[Crabby Jim]

Damsels are very hardy but will eventually become a pain in the butt as they become very territorial and aggressive even to fish way bigger than themselves. I would go for an Algae Sailfin Blenny if I were you . You will probably want to get one eventually anyway they might not be that colorful but they are very cool to watch, very peacful and very useful in a reef tank.
Firefish are nice too colorful, peaceful and cheap. Chromis are cheap and peaceful. Yellow Tangs are nice but can be bossy to any other tang you add later (unless the yellow is smaller than the new tang) I would find something that you like and "make a post before you make the purchase " to be safe.