Ok...I royally screwed up when I tried to post to the subject below. It looks as if I added to the original post instead of offering a separate comment.

Anyway, has anyone thought about Jason Isaacs as Loki? This guy has it down to a T. The arrogance. The snide look. Granted he's probably a bit older than what you guys are looking for but I still say he'd be perfect. Just my two cents.