Its been many years since I kept marine fish, but I remember my most favorite fish to be the Clown Trigger. I kept him in a 58 gal Oceanic tank. Tankmates included a Gold RI'm Tang, Coral Beauty & several damsel fish. Never any aggression problems.
I have a Picasso trigger in my oceanic 75 gallon with a maroon clown, sixline wrase, coral beauty, and a blue velvet damsel. They all get along well with the only aggression coming from the maroon clown when the blue velvet goes near his hiding hole.