Change nothing, and if I'm the NFL, I start threatening to go back to straight up sudden death with a FG if people keep bitching.
Defense matters. If you don't think you can stop the other team, do something different. If the Bills were really afraid they couldn't stop the Chiefs, go for 2 so you're up by more than 3.
Or, you know, play defense for THIRTEEN seconds.
Start OT with an onside kick (so the Chiefs have a shorter field, thus less plays for your defense and less risk of them getting even more tired) and call timeouts frequently to rest them.
There are so many things the Bills could have done differently, fuck changing the rules for one game.
The only thing I'd really be okay with is a "halftime" between end of the game and OT. Even saying it lasts a full quarter is a step too far because...then what? What if the Bills and Chiefs each get one possession each OT period and it goes on forever? The longer it goes, the less likely the defense is to make a play right? That's the whole crux of this argument.
IF we went to a full OT quarter, if its still tied, I say let the kickers decide it with the football FG equivalent of a shootout.