Mouse
Good points about sun protection.
I don't understand how such a small person as yourself manages to keep warm carrying such "light" gear.
Sure acclimatisation makes a huge difference - one of the reasons I live at 4,000 feet.
I also think your size and and age drives you to make a lot of weight decisions that I would not. Of course if I were smaller I might do the same thing. The theory being that a 180 pound person can carry twice as heavy of pack as a 90 pound person and its the same percentage of body weight. Since I do have a huge pack, I can pack a down coat and down pants and not even have to stuff em, and since I always tried to get goretex shelled down garments, all I gotta do is pull it out and slip it on. I would never go above 8,000 feet in the Sierra without being prepared for freezing, snow and hail.
But then I'm always prepared for what happens.

Again - footgear. It has to be snow worthy.
Mouse - what do you wear on your feet?
Jim