A couple answers on the pants:
1) What size waist would these fit?
They have belt loops and an elastic waist, with velcro tabs so you can adjust an additional 2". The pants have side zips just long enough to form a drop seat, and the velcro tabs are at the top of those. I have a 34" waist and they are one 'size' too big, so I'd say minimum 36". Max would be 38 or 40? I will measure them for you. The inseam is around 32". If you have XL Patagonia micro puff pants, well, that's how they fit. Length, waist, legs, everything.
2) Is there any fabric or insulation on the inside of the shell material?
The material is a nylon / spandex blend with some kind of DWR. It is uninsulated with a very dense face. It is not your typical thick, spongey softshell, but more like the old Patagonia Ready Mix jacket, if that helps. The knees are double material. The cuffs have a grippy rubber / elastic material and a place to attach gaiter cords. Also snaps to tighten the cuff around your boot, and ankle zips. The hand pockets have a mesh liner. The big cargo pockets have an adjustable shock cord so you can tighten them closed like a stuff sack, and a velcro flap.
3) Do you know what they weigh? Thanks!
I don't have a way to weigh them, other than a bathroom scale. The Patagonia Simple Guide pant weighs maybe 13 oz.; these add two cargo pockets and some zippers and extra material to accommodate layering. Plus the removable suspenders. I'm guessing they are a pound? Think tough breathable outer layer, rather than all-in-one piece. They don't have a 'brushed interior.'
Hope this helps! Let me know if you want me to dig them out and take photos.