I posted a similar thread like this last year in 2014. I was a stormcloak/guard. Came out pretty well. Now I'm trying to figure out what to do this year. I would be a draugr, but I'm not the skinniest person in the world.
So far my possibilities for this years costume relating to TES are
-Dragon Priest (before its death as I do not have the physique of a skeleton ha ha)
-Miraak
-Mythic Dawn (just the red robes)
-Your mom (just kidding)
Would love other ideas if you have any.