Regarding the interval between the Regionals and the Frozen Four, it may seem like two weeks, but it’s not even that, because under the current system, two regionals have their finals on Sunday. And the two weeks isn’t really two weeks, because the Frozen Four actually starts on Wednesday. So if you move to a nominal one week between the Regionals and the Frozen Four, here’s the worst case, which would be for a team that travels to a Regional that has its final on Sunday:
Sunday: Regional finals
Sunday night, or Monday: travel home
Tuesday: Travel to Frozen Four city
Wednesday: Practice/skate on Frozen Four rink
Thursday: Frozen Four game
And that doesn't take into account the difficulty of making the travel arrangements, and the fans who don’t attend the Frozen Four unless their team’s there. They'd have three days to get tickets, make travel and accommodation arrangements and to get to the Frozen Four city.