There are probably more species of wrasse that any other fish in the ocean so you have a lot of choices. My favorite wrasse has always been the Radiant Wrasse and they are peaceful. Yellow Coris, Exquisite, Christmas, Melanurus, and Rhomboid are also good choices for a tank that size. Of course you have a whole sleu of fairy and flashers. Flashers need to be fed a bit more IMO to stay healthy and they make you woosy watching them dart all over the place