My house has the same siding and windows!!! Very, VERY nice work! That is my next decision....what color to paint the exterior. OR do I patch the peeling paint with primer, put off painting the exterior another few years and remodel the kitchen next instead....sigh
I've got a friend in the specialty paint business who would know what to do. There's gotta be an easier way than sanding everything.
I wonder if you could media/soda blast the hole house? Probably not that expensive to get a mobile blaster in for the day to do it for you.