Instead of 4 Nations, NHL should have a 7-game series between Canada and the US while the other hockey countries scrimmage
Main problem with 4 nations is that so many hockey countries were excluded from being beaten up on by Canada and the US. To fix this, I propose two separate series:
Canada vs. US in a best-of-7 would be great, best of the best going at it for 7 games.
And then you can still include all the other countries by selecting 2 scrimmage teams from the rest of the world, and letting them play their own series in some other foreign country. How long the series is doesn't really matter because the main goal would just be for these players to have fun.