NHL GM meetings start today. Elliotte Friedman has said that some of the big focuses will be 3-on-3 OT, NCAA & CHL, and injury risk from international breaks.
If there's Mass migration from New England into the QMJHL, it would fundamentally reshape the character of the Q in particular. Keeping Americans and Canadians in their own nations (with limited exceptions) until they're 18 should even that out.
Although I'm not sure 16-year-old Liam from Plymouth, MA would be as eager to join Rouyn-Noranda or Val-d'Or as they would to join Charlottetown or Cape Breton. Which is a whole other issue.