I took a look at my winter jacket tonight. It's made mostly of a windproof softshell fabric with fleece bonded on the inside, along with a few non-windblocking panels in key areas (upper back, underarms and sides of torso, etc.). All of the seams are flatlocked. The sleeves are extra-long and sort of a modified raglan style. The bottom is hemmed, with ~6" of elastic at the center back to help it conform to my body and stabilize the exterior pockets. No grippers anywhere...

Hope this helps, and I can't wait to see your finished jacket!