I did this last year and started for this year, but have backed off due to some issues I found.
http://www.operationsports.com/forum...d.php?t=513261
Got half the teams named, correct height/weight, re-rated accross the board, used OL as DT's so they look the part etc.. etc... and Exported each team as I finished them so that I could start a New Franchise and match up rivalries etc...
Got teams playing like they should with Playbook's etc...
Only to find out another "Lazy" limitation with EA's game.
You can't take exported teams from a Franchise into a New Franchise.
What is the point of Exporting a team?
Also, if you create/edit players and put them on your created team, and then take that team into a Franchise, get ready for the game to delete some of your hard work and replace them with in-game generated players with goofy bodies and shoulder pads.
There are other things, but I'll spare you as to not rain "Heavily" on your parade.