1. They purposefully tried to avoid stages based on home console games. The few that appear are exceptions.
2. Ice Climbers were cut due to hardware limitations and belonging to a dead franchise. Snake could have been cut for several reasons, but in any event there already are three non-Nintendo guests, which is more than enough. I agree about Mewtwo though, while Wolf could go either way.
3. I don't understand WHY a mode that you don't even have to touch turned you away from Brawl. There are plenty of fundamental gameplay elements that should have the same effect.
4. Beause otherwise people would be allowed to express their creativity and force you to play everything from 1 minute to 99 stock matches. And if you want item matches to count I really don't see why local matches won't suffice, considering skill is not a substantial factor.