Rule Changes

Baseball :
Balanced schedules
Salary floor
Top 5 picks go by lottery. That is, the worst 5 teams put in lottery tickets equivalent to how many losses they have. Then the commish draws for the first 4 picks.

NFL:
Play without pads or helmets. Let them play rough, but these pinpoint rule changes will do nothing but neuter the game piecewise.
Otherwise, pay retired players more, so they're not upset and won't sue the NFL for a gagillion dollars
Put an asterisk next to the 2001 Patriots championship, because they finally got rid of the tuck rule. What a bunch of $$$$$##!@#

NBA:
1st round playoffs to 5 games, all other rounds 7 games.
Flopping is a 1/2 game suspension. Seriously half game. Player can't play for the first half of the next consecutive game. Pay is not suspended.
Coaches get 1 challenge per game, if they lose they lose a time out
Flagrant fouls require video review
Bring back hand-checking
[something about free-agents]

NCAA basketball:
Stop the fouling at the end of the game. Last 2 minutes, automatic, 1 foul away from the ball = Opposing team gets 1 free throw and posession

Soccer:
Add another ref
Goal line technology
Suspend a player for 1/2 a game if he's found to have flopped. See NBA. Half a game which is the next consecutive.
Tournament: Instead of 1pt for draws universally, if the game is 0-0, give both teams 0 points.