If your planning on making it a reef tank then count on keeping 0nly 3-5 fish max. And since you already have a fairly large fish in your tang, I would keep the others small. If you plan on keeping any shrimp then I would be cautious with any wrasses and hawkfish. Also forget about any butterfly and angel fish as they are generally not reef safe.
Some nice reef safe fish are Canary and Midas blennies, Royal Gramma, Six line wrasse, any of the fire fish, flame, coral and longnose hawkfish to name a few. Beware the wrasses, hawkfish and fire fish are jumpers, so you will need a top for the tank.
If you dont have one yet, you should buy a good book on marine fish such as
A PocketExpert Guide- Marine Fishes, there is also one for reef safe fish too. _________ 75g reef with Nova Extreme 8 bulb HO T-5 lighting, refuge, Remora skimmer, DSB, Seio powerheads, Acro's, LPS corals, assorted zoo's & mushrooms, Yellow Tang, Maroon Clown, Blue Cleaner Goby , Cleaner, Fire and Sexy Shrimp, Coco Worm, T.Crocea Clam, Derasa Clam
120g FOWLR, 260w Orbit power compact lights, Remora Pro skimmer, 30g DIY Sump/Refuge, DSB,Seio Power heads, Powder Blue Tang, Purple Tang, Flag Fin Angel, False Eye Puffer, Copperbanded Butterfly and a Moorish Idol  | 
what else for the list? 
