Livestock Plan

So I am getting ready to add more livestock. I currently have a 70g FOWLR with 85 lbs LR and 20lbs LS. I have 2 clowns and 3 chromis. My wife wants some vibrant color added. Can I add two more blue reef chromis with the blue green chromis? Or maybe a couple yellow tail damsels? I am worried about compatibility of damsels with the clowns. I am concerned about the blue chromis because I don't want a majority of my stock of one species. My stocking wish list is this: 2 clowns, 3 b/g chromis, royal gramma, chalk bass?, and a yellow or blue tang when I get a bigger tank. So would 2 blue chromis or 2 yellowtail damsels be OK and which one will be safer for my tank?