What will the combat system be like? (SAO sword skills vs. Alpheim skill-based combat)
Will there be different races?
If so, basic RPG races or anime races? (cat-people, etc.)
How do you plan on implementing magic? (gesture based, voice command based, etc.)
Side note: if you're still trying to figure this out I have a few ideas that might help
Will there be unique skills here, like in SAO?
What will basic story progression be like? (In SAO, it would be clearing the floors.)
Will characters be fully customizable or based off of our irl appearances?
If you guys don't have the answers, that's okay (I know you're focusing on SAO right now), I just wanted a bit more info on your other project.