I usually play on the Stormcloak side but I think they are probably making a mistake in going to war against the empire. Yes the empire are in a difficult situation the threat of the dominion means they cant send large numbers of troops to Skyrim so its a good opportunity to make a bid for independence. Yes they have betrayed Skyrim by agreeing to ban Talos worship and allow the thalmor to roam freely enforcing that ban. The problem I have with the Stormcloak uprising is that the white gold concord is not a piece treaty its more of a truce. The time is going to come when the Dominion and the Empire and the empires allies (possibly an independent Skyrim) go to war. When that happens every person that has died in the empire vs stormcloak war is one less person available to fight the dominion. That's why the thalmor are happy for the stormcoak vs empire war to continue and for it to drag on as long as possible. Ulfric and his supporters may be upset about the banning of Talos worship and this may be a grate opportunity for independence but it ignores the bigger picture and ultimately makes a dominion victory more likely.

My feeling is that the Stormcloaks and the Aldmeri Dominion are doing what they believe is right but the empire is a puppet just doing what they are told. Take that as you will but I believe that you have to fight for your right to party.