The stormcloaks are the only ones with the balls to stand up for their beliefs. The empire took the low road and rolled over for the Dominion. They gave up belief in one of there gods because someone said they would kill them if they didn't. Anyone who will do something like that doesnt deserve to rule over anyone. Stormcloaks would rather die than give up what they believe in and that is what makes them the right choice. Granted Ulffric isn't the best guy but no one else was willing to step forward and make the hard decision to stand and fight.
He who fights and runs away lives to fight another day.
Ulfric has a crippling lack of foresight and perspective. He follows his heart, not his mind. He also has a problem taking "no" as an answer, and also has a troubling "with us or against us" mentality. He also mistakedly claims himself king. Elisif has claim to the throne... she does not claim the throne as hers already.
To quote Odin from the recent Thor movie... Ulfric is a vain cruel greedy boy.
Also... Near the Rift hold Imperial camp, I found a little curiousity... a Talos shrine, surrounded by imperial legion paraphenalia. In all likelihood, a secret shrine for the encampment out of sight of any visiting Thalmor jackboots. It seems that the Legion has as much regard for the Concordat as the Thalmor do for Imperial sovereignty.