How about a bicolor blenny or a small wrasse like a six-line. Those would make a fine addition.
50 gallon saltwater fish only...1 mated pair yellowtail damsels, neon dottyback, tomato clown, huma trigger, lemonpeel angel, 12 stripe wrase, bi-color blenny, dozen or so hermit crabs-scarlet and mexican, cerith snails, turbo snails, orange linkia starfish, 50 plus pounds of purple-pink coraline encrusted rock and a few mushrooms.
Redsea prism protein skimmer, 404 Fluval, UGF
with two 201 powerheads.
7 gallon tank with 6 pounds of live rock and countless brittlestars, 5 hermit crabs, snails and 1 False Percula Clown fish and Camel Back Dancing shrimp