I agree with TimO, Get what you like, But heres some suggestions: Clown Fish are great!
Royal Gramma, very easy to care for and very pretty!
Banner Fish are eye catching (to me)
Damsel's are eye catching, but I'd stay away from them
Blue Hippo Tang, but you'd need to move them to a bigger tank after a while, they need tons of space!
Yellow Tangs I highly Recommened!
Stay away from triggers, they look great but if you want many small fish; their just no tank-mates lets say!:happyfish