I have been evaluating lightweight mid-height boots as I like the ankle protection. I am packing the same weight range as you are on the JMT. I have hiked the Sierras the last 10 years. The ones high on my list are:
Keen Mid Targhee II boots with eVent (hard to find, Keen has switched to Keen.Dry but I found a pair last Sunday) – 16.5 oz.
Keen Mid Voyager boots (not W/P) but very breathable. 16.5 oz.
Asolo Everland GV boots (18 oz) – has Goretex
Asolo Lander GV boots (20 oz) – water resistant material only (the Goretex version of this boot is the Spyre GV by Asolo and looks the same/weighs the same)
Inov8 370s (13.5 oz) (reviewed on BPL)
The Inov8 and Everland boots have less rigid soles than the Keen/Lander boots.
I have hiked the JMT/HST with the Keen Mid Targhee but not with the others — would like input from those who have.
PS, when others recommend boots, please indicate height of boots (full, mid, low). Thanks!
ps – I have wide feet and appreciate knowing if the boots accomodate wide feet. I should note the Inov8 are narrow and I had to go to size 10 to get a fit. Others are fine for me at size 9.5