"Smarter" helmets? It would seem to be the most accepted remedy but they unfortunately don't seem to exist, so that's the first hurdle I guess lol
That might help with concussions, but it's not going to help with the various physical problems below the neck that players get. Players are constantly demanding greater post-retirement medical benefits because they know the physical toll the game takes. If that is their stance, then they should be thrilled that Goodell is trying to make the game less violent.