Re: Surtur's Role
Yes, they could retcon Surtur's age to predate the universe as well. The Eternal Flame he uses to light the Twilight Sword is supposed to be at least as old as "the dawn of time," and Surtur was around for that (Odin stole the Flame from him way back then). And wasn't the Eternal Flame supposedly one of the treasures shown in Odin's Treasury in the Thor deleted scene....?
So yeah, it could work. But if so, you're *definitely* looking at a MUCH larger role for Surtur in this film than just a cameo or setup for Thor 3....he's likely *The* Big Bad of the movie.
THE COTTON AVENGERS
...They move like slick cotton on oil.