Welcome to AA! The next thing I'd put into my tank would be a nice sized pile of live rock (www.liverocks.com
is *great*). That will give your fish someplace to hide, aid in the filtration and provide a natural environment to the fish.
The guideline for saltwater fish is and inch per 5g of adult fish minus the tail. www.liveaquaria.com
has great information on the temperment of fish and their hardiness. It is a great place to look for ideas on fish.
Not wanting reef really opens up some possibilities for you. We have 3 chromis in our 120 and they're great fish. I've heard to keep them in odd numbers and 8 of them (24" of adult fish) would be a lot for a 75, given a recommended bioload of 15" of adult fish (lots of people go over that, but you don't want to go *tooooo* far).
We also have the spotted cardinals. They're interesting fish. They just hover in the water column for the most part. Our yellow tang is an avid swimmer streaking across the water like lightening at times. I don't have much experience with the rest of your fish since we stayed reef safe with our selection (and am so glad we did, adding a little coral to the tank changed its personality dramatically).
Good luck coming up with your final fish list. The hardest part of this hobby second only to waiting is limiting the number of fish you put into your tank!