Some good points but I feel you forgot to factor in the most important political power: You. As a Dragonborn you are capable of wearing the Amulet of Kings and able to light the Dragon Fires/Pyres. Which means you yourself could become (technically) a new Emperor and unite the crumbled dynasty behind you. Along with possibly being able to unite currently warring countries in order to defeat the one power everybody hates: The Aldmeri Dominion. So siding with the Stormcloaks could technically be more epic if a longer run of the game were possible.
Come to think of it, I'd like to see a big mod in the future based on the Thalmor.
Well, I haven't gotten that far in the Main Quest yet, haven't even talked to the Grey Beards. So, my opinion is mainly from Lore knowledge and reading the in-game books. If I actually turn out to be Dragonborn (

) then I would much rather try to improve and re-order an intact and existing Empire than try to build one from the ground up.
I think you have got it all wrong.
The empire were at war with them known as "the great war". This was as you have probably heard one of the bloodiest in empire history. The empire and the Talmor are at a very thin line of peace with each other. That "hanging out" talk you got there, I have no idea where you got that from. The only reason the Talmor have an embassy and justacars walking about is because to see that the empire is following the white-gold concordant and suppress people that still oppose the Talmor.
Exactly and bravo. The in game book "The Great War" opened my eyes.