airwalkrr
Adventurer
If all the players have meaningful choices to make, the game is balanced. And yes, that could mean a game of RIFTS where one guy plays a Glitter Boy and another a City Rat.
While such a thing is possible, it's far from easy, or likely to find. In most cases I think it is the GM's responsibility to step in and say either:
"You may not have fun playing a City Rat in my campaign. It's going to be mostly combat."
-or-
"You may not have fun playing a Glitter Boy in my campaign. It's going to be mostly stealth and intrigue with little chance for combat."
GM responsibility goes beyond just showing up to recite read-aloud text from an adventure. He should assist in the character creation process to ensure everyone creates a character that can contribute.
For example, when I began my Ravenloft campaign and one of my players wanted to play a ranger, I explained which favored enemy choices would be appropriate for a Ravenloft campaign. Sure, I could have let the player (who knew nothing about the setting) choose blindly, but I had a greater responsibility than that. It's the same reason you don't let the new player choose a fighter when they have a 10 Strength (or you let them swap Strength with one of their higher stats). Now if a player WANTS to play an underpowered character because they enjoy it, that's one thing. But it is every GM's job to make sure every character has a chance to contribute, and that starts with character generation. That way, situations like the one Garthanos brought up don't happen.