This raises an important point: What is the purpose of divisions? Is it just another attempt to map the NFL onto fantasy? In your case, it sounds like you have four divisions, which seems particularly silly. I successfully lobbied my 16-team league to switch from four to two last year, but honestly, I don't know why we have them at all. My 14-team league did away with them completely a few years ago, mostly because Yahoo's default scheduling is a mess (it will have you play some teams twice, regardless of division, and other teams not at all), and the commish didn't feel like adjusting it manually every year.
The one scenario where I think divisions make sense is if you have history behind the rivalries AND if you play everyone in the division an equal number of times. For example, if you have a 10-team league, each divisional opponent can face off twice, plus a single game against the teams in the other division. Heck, you could have a 16-team league with a 14-game regular season consisting of nothing but divisional match-ups. But if you're just doing it to mimic the NFL, why even bother?