Red tail or sargasum triggers are considered by most to be reef safe. I would add inverts , especially shrimp before it tho. Most qt fish for 4-6weeks depending if treatment was needed
Watch mixing angels. You can get 2 maroons, but it means buying a pair together. A mated pair ideally. Of your possible fish i would do a fox and potters. Personal choice on those lol
A 75 is a good start. If you want coral a good lighting system is needed so do your homework on that. You will want a sand substrate, not crushed coral. You will want a few lbs of live rock to help seed your base rock