Here's what I actually have in my 210. Except for my concern about being overcrowded, this is a great mix. The fish are very interactive and the eels are out a lot.
In the tank now:
6" emperor angel
4" porcupine puffer
5" dogface puffer
8" black tip grouper
6" Australian harlequin tuskfish
24-30" Brazilian dragon moray
3.5+ foot zebra moray
Going in soon: 3" niger trigger and blue spot rabbitfish
For the most part, they get along, although the HT gets picked on by my angel and porc puffer. Hopefully with time, he'll get a little more assertive. (BTW, relative to elecbzerk's comment, a harlequin tusk IS a wrasse!)
Look at pictures of danorth's Coris wrasse. It's a gorgeous fish, and has been at about 12" for several years. Be sure you get the right species - some Coris get over 2 feet! If I had more room and a deeper sand bed, I'd get one of those.
Another nice fish is the foxface lo (as a suggested yellow fish in place of the mimic tang) - economical price, hardy, peaceful but can stand up for itself, eats algae, great color.