Agreed. The rewards and the quests themselves were very underwhelming, no unique armor/weapons or really even a "thank you" after they were completed, despite the fact your character single-handedly turns the tide of the war in one direction or another.
When I found in a ruin the special Corinthian style imperial helmet, I hoped this helm was part of a one-of-a-kind armor found somewhere or given as reward during the imperial quest. Imagine my disappointment when I did not even get Tullius nice armor.
The only way to get Tullius armor is to... side with Ulfric! Brillant! It reminds me of Shivering Isles where you got the opposite faction armor as reward. How [censored] is that?