Hi Julie,
thank you!

I'd definitely take the 20F bag. And definitely only carry 1L of water up to trail camp (more specifically, the springs on the switchbacks). Otherwise, do have water containers for 3L for the trip to the top.

my trip report from last year.
http://www.whitneyzone.com/wz/ubbthreads.php/topics/7208/1

I always bring too much food. I really do recommend going over your menu for the trip to determine if you are bringing extra. My bag is always really reasonable until I put the bear vault in. Just looking out for your Sherpa. smile
Tom