I always refer back to the wisdom of TV shows for these kind of questions. In this case Spartacus: Blood and Sand comes to mind. What was that final episode called again? Owh... that's right: KILL THEM ALL.
Kidding, OT: I had the same problem in the beginning. I play a Nord (always do my first TES game playthrough as a 'Ragnar' the Nord.) but i really don't agree with the:
Skyrim belongs to only the Nords idea. Besides, someone who is nicknamed the Kingslayer gives me shivers (Owh Game of Thrones).
With so many different species around (not even humans of different backgrounds, but freaking lizards and cats and elves, oh my!) it's even worse to proclaim that 'Skyrim belongs to the human Nords'. However Imperial rule isn't what it used to be, bending to the will of the Dominion and their 'you cannot worship Talos' idea. So i decided to keep the quest untouched. Maybe return when i found more info. And that's just what happens if you follow the main quest far enough. After a certain party quest i made my mind up and the decision was pretty easy.