In my personal opinion it is completely rediculous to allow countries entering two teams in one division.
If this is allowed you can't possibly consider this tournament to be a WC, but it becomes a regular tournament where just anyone can join.

As for making the tournament shorter. I think they can still run over two weeks, but when putting all Elite games in one week and masters and juniors in the second. There will still be the cost saving benefit, but Elite teams are not obliged to stay for two weeks if they don't want. Of course less people would be present at the party and part of a worlds charm is seeing old friends again, but quit some players and federations would wine less.