In the winter both Mike and the Goat have taught/turned me on to down filled pants and booties. They are an investment though but extremely light, compressible, and toasty warm out in the boonies. A big difference from carrying snow pants. When out and about, I have carried my precip-like pants as a water proof layer but on sunny days while we are putting in miles it can get too hot- just like snow pants.
For a jacket, the Marmot Zeus seems to be the way to go at this time. This we carry year round now, it is compressible and a great pillow and better than fleece- in my opinion. And a precip jacket covers the upper body as a outer layer when it is wet or snowy.
For next to body:
I also like and have the silk. It is good. Issue for me is having to take the stuff off in the morning as your start your hike cuz you can overheat in the stuff once you break trail. Then it feels pretty nippy cuz you gotta take off other layers to get to the silk. But it is good stuff.
I also do what Mr. bbb suggested I go to Target and get the synthetics as simply shirts I wear. Wish they would stock just one solid color- they seem to now be stocking multiple color running shirts.