[JohnM99]

A stellate rabbitfish might be interesting - there is one for sale at J&L right now.
Although niger triggers can be interesting, maybe a picasso, assasi or blueline might be more interesting - or a clown trigger. A clown filefish is beautiful, but probably needs a bigger tank.
So many to choose from!! I wish I had a new tank to stock!
As for size and number, your list does seem a bit long, but you can always sell one if the tank gets too crowded as they grow. Hard to add a fish amongst other aggressive fish later on sometimes.
Sounds like that will be a messy tank - need lots of skimming / fuge / cleaning - but very interesting.