If you can still find it, try wool pile. Not the WWII stuff, they used the same design as the synthetic but used wool thread (real good stuff too). Light as fleece, but all the advantages of wool. Helly Hansen used to make it for the Swedish Army. They started it, I am told, because the synthetic dld not work well when they could not wash it every day or two. I'd love to find some more.

Respectfully,

Jerry