I am in the same boat with a 180. I tried anthias but they all died. I think a group of firefish gobies would be cool but they say don't put more than one in a tank. I wonder if anyone has placed 6-8 in a tank though.
I currently have a clownfish pair, 2 hippo tang, 1 purple tang, 1 yellow tang, 1 solar fairy wrasse, 1 flame angelfish, 1 splendid dottyback and 4 chromis. I want to add more chromis but also want to add more color that's why I went with anthias but already killed 8 of them (never had anthias before so wondering if they are more fragile or just my bad luck). I am thinking of adding pairs of dwarf angels together and also some wrasses but the prices have gone up so much lately. I'd love to add a bunch of cardinal fish as well but I am not sure if they will survive the current.