Glasgow would be so convenient for me, I really hope they get it.
Stockholm would be next best, not too far and I've never been to Sweden - I'd love an excuse to go there. (Assuming I don't make it there for European championships, I'm not expecting to)
Helsinki would be good too. I love that place, love the food, and Finland is a beautiful country with trees everywhere - I mean, EVERYWHERE.
Sochi... I won't even consider going there - it's just too far for me, and too "middle of nowhere" :-/
Anywhere but Sochi. Hackensack, NJ. The Gobi Desert. Mars. Really, anywhere BUT Sochi. ESPECIALLY for the Worlds that determines the number of entrants for the next Olympics.