I love wrasses but I would caution on adding a Melanarus if you have snails, hermits, and shrimp. Besides the carpenter wrasse mentioned I would also recommend the C. solorensis, C. lubbocki, and C. cyanopleura as they are all peaceful, active, and I find them hardier then the P. carpenteri.
A Foxface if on the smaller side starting out would be good. They help control algae and are very peaceful community fish.
A male Squareback Anthias, P. pleurotaenia, would make a nice center piece.