One area of potential concern is how the "rest of the best" team gets selected. Will be interesting to see how they do it. Will every country automatically get a spot like back in the NHL All-Star days, and the rest of the spots being selected more on merit? Who will do the selecting?
I can see a potential problem coming up - bribes. Apparently, lots of hockey players in some poor countries often have to bribe their way onto lines and playing time, etc. - at least if you believe the words of Mike Danton:
http://www.mikedanton22.com/kazakhstan-true-story-2/
I can imagine some poor eastern European teams may have the same issues. "Want to be on that team and have a chance to showcase yourself to NHL teams and maybe become a hero? Give me $10,000!". Hopefully the selection to those teams have a few safeguards. Maybe I am just being paranoid, but would hate to see a scandal.