I already thought he was lame for having religion as the main reason of his rebellion, but after having contact with the Skaal I definitely confirmed my hypothesis. He claims to be a "true nord" and fight for the right of worshiping Talos, when the true nords are actually the Skaal, who preserved their ancient culture and beliefs on the All-Maker, not even Harmaeus Mora himself had enough knowledge on their tribe. The Stormcloaks are like a pack of mongrelized barbarians compared to the Skaal. I'm not taking sides on the Civil War anyway, as both of them are wrong, but still, Ulfric is damn lame.

That civil war lame in general, no real change to the game anyways.