that's a damn fine interesting and original idea. it would give teams a real incentive to get better (to make it a real incentive, the 2 at-large spots would have to be doled out only amongst the top 4 divisions. ) but why punish good teams and make it really tuff on them by lumping them in with teams that also really really good. and because of off-season braziness, a team can improve/change significiantly over the off-season so i'm not sure that last year's w-l record is indicitive of who should be in premier divisions the next season.

this system may also go too far in the other spectrum of rivalries, in the current system, you can pretty much only establish a rivalry with teams in your division, and that is too limiting. but in this system, rivalries would change every year because there would be no continuity.
but it's a great idea.