One idea that was floated a few years back and immediately laughed into oblivion was to have rostered weeks off for players.
Effectively, a player can only play, for example, 18 of the 22 games in a year. The other weeks they're entitled to go away and do what they want.
And we have a very good example just this year in Josh Schache, who gets a week off to visit his family and comes back apparently much more confident about his future and re-signs with his current club.
It's a long, intense season and allowing players to step outside of it for a short time seems only humane.