Don't restrict the available classes.
People naturally assume we'll only be paying for specialty items and gear. But practically anything in the game could be set up as a microtransaction. Maybe we can all start out as peons in the Rebel or Imperial army, but to become Jedi we've got to pay a couple bucks to unlock the class or a new character slot (like Guild Wars). This would create a horrible, resentment filled, class-based system where rich gamers get to play the cool classes and the poor gamers play the drone classes. I can't imagine BioWare doing this, but you never know. Let's hope they don't.

I dont see a problem in that, they said that playing other class will be how play a different game. You can buy only the main game and the jedi game and when you ended buy the bounty hunter game, that is not unfair, they can sell complete classes, not necessarialy knee caped classes, how yu presumes. All selleable classes must be equaly cool, I doubt that they sell more expensive a class based in some subjetive coolness. Some people hate jedis and instead likes elite troopers.