Achilles are difficult to keep, in, my research. Best bet is to find someone selling an established one.
Scott's fairy wrasses are nice. But will get aggressive towards new wrasses addition. If you want one, add it as your last wrasse...and even then it can be a gamble.
Yellow tangs are great.
Labouti wrasse are peaceful and rather colorful (i have one and have been told it's one of the better looking in my tank)
Powder blue tangs are dope....but like with all tangs, prone to ich