>>1381654if you sweat a lot you should probably look into synthetic materials.
base layer should be tight unto the skin and synthetic, wool is hygroscopic and doesn't allow moisture transfer to outer layers that easily.
also down jackets are not suited to the aerobic phase but to when you stop and remove the backpack.
this is what I wear when I do activity in the winter, up to -15C
base layer: long sleeve synthetic thermal upper and lower body, elastic to have a better fit and moisture wicking.
midlayer: microfleece/polarfleece depending on how is cold, I usually can do with a microfleece
outer layer: windproof softshell
lower body: alpinism pants with gaiters
outer shell: gtx jacket, to use only when shit hits the fans
head: woolen hat + fleece neckwarmer which can double as a hat.
gloves: 2 pairs of undergloves+ 2 pairs of gloves, because they will get wet
As for the nighttime, I suggest you bring some spare clothes you will use only for sleeping, so they will be moisture free and clean.
as for the jacket size, just try it on with everything you think you will wear during the hike, don't get it too large or you will lose heat too rapidly but not too snug you can't move.
