The stock atlantis goes one size bigger, in 26.

I wanted to get a touring bike for my trip, but it was a bit hard to justify given that the geometry of my Nishiki Cascade was so close already, except for being not as tall. Length wise it was 42". The 700 C does seem a lot faster, I rationalized it somehow, but for where you are going, that doesn't sound all that big a part of it.