I was thinking about this and it was, why not put Crazy Hand in the game as a boss with Master Hand?
It's a bit like this: In Melee and Brawl, you can fight both Master Hand & Crazy by:
-Not losing any lives.
-And some other things that I don't know yet.
Also if you lose to both of them, you have to fight only Master Hand.
So, should Crazy Hand join in as a boss with Master Hand?