Thanks for the responses.
Just to clear things up, I will be using most of this rep for my Graduate school auditions so Bach is a must as is Beethoven.
The suggestion for something "crazy modernist" is good and deserved, but I was thinking more about what would display greatest amount of variety and I figured the Messiaen was 20th century enough, though not too unknown or off the wall, and contrasts with the rest of my program well. I may switch it out for something more modern in the end, although I really do like it.
Anyways, thanks for the thoughts.