Louie G.
Smash Hero
Eh...You can have any excuse for make a mario game, it doesnt matter, bowser and peach are just the most used.
But cranky is different, is a great part of the experience, is what gives flavor to the game and a great part of dkc idendity.
Dixie and K Rool may be more important for the argument, but for the actual game, they really are just excuses.
And well, cranky actually start the whole donkey land series so...
I don't know how DK can't be DK without Cranky but Mario can be Mario without Bowser or Peach.