I personally hate QB kneel downs at the end of the game. The NFL should remove this from the game by implementing the following rule:
Any rush for a loss of yardage inside of 2 minutes of the 4th qtr will stop the clock.
This will force teams to try and run for yards or pass it in order to maintain possession. It will also give teams with no timeouts left a chance to stop the clock with a stuff in the backfield. That would create tons of excitement and extend games. I think this kind of rule will create more great finishes instead of boring kneel downs that milk the clock.