The Super Bowl
MLB final - 7 games
NBA final - 7 games
NHL final - 7 games
NFL final - 1 game
Think of all the money the league and finalists would get if it was best 2 out of 3.
One game at each winners home field and game 3 at a neutral site.
Would be exciting to see, and season ticket holders would be rewarded with a one game Super Bowl playoff game.