Well, I think you should look into readjusting your schedule and getting it done, loads of fun for sure. The theme of your costume is something that only you can come up with yourself and I have faith in you that your choice will be exactly what it needs to be.
Marty McFly? (Back to the future)
Sam Beckett? (Quantum Leap)
Billy Pilgrim? (Slaughterhouse-Five)
Dr. Rick Marshall? (Land of the lost)
I'm sure you can come up with better options.
I can think of a couple literary options.
Does Gulliver count?