Thank you all for your advice so far, and of course I'm going to have the body in hand a month or two in advance, even if it's the D5200 (already owning the D5100, my fingers will fall to the right places automatically). And the 35 f/1.8 is because I'm not going alone, but with some family, so at night it's useful. With the D7000, I'm sure I can get great images out of it on day one being intimately familiar with the sensor, but of course they'll only get better after a month.
I had the 55-300 and 55-200 at the same time before, and I ended up keeping only the 55-200 as the 55-300 looked soft beyond 200 mm, even supported, so it didn't really give me better enlargements and just weighed more than the 55-300, plus with the 52 vs 58 mm filter thread it was a bit of a pain, and it still lacked quick focus override, so I ended up using the 18-55 and 55-200 pair as a mid zoom and tele zoom and got rid of the 55-300, figuring I'd purchase a new one when I finally needed more reach. The 70-300 only weighs 7.6 oz more than the 55-300, so that's where my thought ran to first.
As another thought, does the 70-200 f/4 work with a TC? It's new enough not to be listed, but being faster at f/4 it should work with the TC-14 on any body and the TC-17 and TC-20 on the new f/8 AF bodies, in theory, anyway. Also, I do own film bodies and hopefully will own an FX body soon enough, so there's that long term advantage.
As for packing clothing, yeah, I know how to pack; as an Eagle Scout, I've been backpacking in my youth more than a few times. Not only fewer pants, but lightweight pants and shirts, and so on. Also, lightweight luggage and I've even gotten down to taking a disposable lightweight razor and toothbrush in order to make room for the camera equipment. If something takes AA batteries, I'm using primary lithium cells. Even my on the road photo backup solution is changing from an external HDD to a fairly expensive flash drive.