NO NICKNAME NAMES. I can always find a good nickname in any name. My partner's mom named her sons to have no nicknames: Jason is now Jay or Jase and Branden is B or Denny, etc. But if you want a name that will usually be said in full (no obviously accessible pet forms for people to pluck out of thin air), try starting with these.
I love SAO. I'm watching the GGO part now in the anime, and I'm going to read the manga soon. People who say your crap because you just watch the anime are wrong. Anyone that has only watched the anime like me is just as good as any other fan.