Coming back to your list of other possible tankmates, I've read a number of posts on R2R that the neon goby is aggressive. So you might want to research more on that one before you add it.
My blue neon goby is one of my favorites. When I was younger I only wanted the rare, hard to keep fish. Now I just like something with personality. The BNG and my spottail blenny are sort of buddies. They don't mind each other, and even sometimes one will perch atop the other. It's pretty entertaining.
I have a tanaka and he is a model species. He constantly is seen picking the rock work and glass. Beautiful tiny tiny fish. In my experience flasher wrasse never keep their color. I have not tried a trio but from what i have read more than likely they will all turn male. I have left 2 flasher males together before but again color seems to fade as they get comfortable with each other. In my opinion fairy wrasse are the way to go. I own a female hooded and even for a female she brings a huge burst of color to my tank.
I must admit that I haven't even been able to get a flasher wrasse shipped in good condition. I feel guilt because I ordered five different flashers, none of which lived more than a few hours after acclimation. My longfin fairy wrasse was inexpensive, relatively, and is quite fun.
I have a Yellow Banded Possum and a Pink Streaked (Pseudocheilinops ataenia)together in a 65. They're buddies. The Possum is a bit shy sometimes, but the Pink Streaked has no fear. I've seen it steal food out of my full size Royal Grammas mouth and dart away. I highly recommend that as a tank mate for a Possum.