I went backpacking with a student orientation group last month. I took a pair of X-T1 bodies, the 16/1.4 and 35/2 lenses, and the 90mm. I went back and forth for a while on the 55-200 instead of the 90, but eventually figured the weather resistance and faster aperture would be more useful than the versatility of the zoom. All of it fit in an old LowePro waist pack, along with a ton of spare batteries.
The 90 got some use shooting candid portraits, but for the most part the photos (
link to gallery) are all shot with the other two lenses. Had I been shooting landscapes, I would have taken the 55-200, of course.
Backpacking and long distance hiking are my chief escapes from photography, so I don't have much experience carrying "real" gear on the trail. I was pleasantly surprised by how easy it was to wear the waist pack in front, put on my backpack, and hike with easy access to my cameras. The weight wasn't a big deal (maybe 5 pounds or so?) and the cameras performed well.