How 'bout putting different challenges per day?
For example, in a tribe of 10 people,
2 will play Guitar;
2 will play Endurance;
2 will play Maze;
4 will play Deal;
so that each person can play the game with their own strengths.
Then the tribe with the higher number of accumulated points gets to win.
Just like in the real survivor, x number of people get to swim, some get to solve the puzzle, throw projectiles, etc.
