... you become the next Talos and start a new dynasty as emperor.

This has to involve kicking the backsides of the Thalmor some, including possibly some elven Deity. The action may involve some trip to Cyrodil or Hammerfel or somesuch & feature a decisive battle against the height of Thalmor might. (It would work regardless of which side you picked in civil war -- even if you yourself are elven: Thalmor are designed as a universal antagonist!)

Also, in line with Tiber Septim's original exploits, this would feature some trips to massive Dwemer conclaves to tap some forgotten power. (Not necessarily a whole new Numidium, and no, no returning of the Dwemer themselves!)

I....I think the sheer horror of this idea just gave me cancer.

err.... elaborate?

Last dlc:

Solitude Guard gets the chopping block