Just going out the door and I'll post later but I noticed you mention eye controlling the computer. I recently read an article about a password system that reads your eye, not just to verify your ID (and we know how that worked in Demolition man) but you move your eye in a few directions as a password, so to speak.
Back: I found this video on a hologram system today
http://www.youtube.com/watch?v=FF1vF...%2Findex%2Ephp
There's also the table top system Microsoft is making.
Along with the eye control thing I mentioned they are also making bionic control feasible. That might be useful to control things. The thing is that you can increase the number of palyers and the number of systems but past a certain point it slows down the game. I believe we are already at a fair level. Any more and you will have long periods between turns waiting for everyone to do their turn, and with many more systems it'll be longer before you meet anyone and longer for things to develop as empires expand until they conflict with others.