No issue with the sixline?If this was my tank I would go with a pair of clowns (love them and classic fish!) a sixline wrasse to control pests (and their colors are stunning, love mine in my biocube) a blenny of some kind (algae and personality) a cardinal fish (since they just float in open water and are cool) and the mandarin!
My biocube:
Clown pair
Starry blenny,
Zebra dart goby
Sixline
Cardnial
3 saltwater mollies
Neon dottyback