I think Mario Kart would actually be less balanced without the blue shell, and more possibly even more frustrating too. The thing is, most of the items hit people in proximity, they especially hurt you if you're part of the pack continually using all sorts of items. If you can manage to get a decent lead, ahead of the pack, the only items you have to worry about are red shells (just drag bananas behind you) and blue shells. So without blue shells, it would make it more difficult to win unless you get an early lead, when part of the point of Mario Kart is that you always feel there's a *chance* you could get ahead and steal victory.
A game I'm developing with some friends:
www.xnagg.com/zombieasteroids/publish.htm
It is largely a technical exercise but feedback is appreciated.
