That sort of defeats the purpose of a sports game. Certian teams are better that others. I'm sure that most gamers "Sim" or not, wouldn't be thrilled if it was just as easy win with the Raiders, as it is with the Saints.
Making ratings matter more won't make stick skill obsolete. The ratings for the defensives players will matter also. So if you've got great sticks skills, and you're controlling Darren Sproles, if someone is controlling a LB, they've got no chance.
It may even draw them into franchise mode; they could draft,scout and sign players that will help them take advantage of their superior stick skills.