Great advice everyone, thanks!

I am thinking I might bring the ski pants for real cold days and around camp, but also bring my full zip rain pants as a lighter outer layer. Maybe have a pair of light baselayer bottoms and a pair of heavyweights? Possibly use the polar weight baselayer bottoms as an insulating layer, and the rain pants over?

I have a pair of Seal Skins socks that I use for skiing. Would these be good with hiking boots? They definitely keep all water out, but I'm worried about them not breathing well.

What about down or fleece socks to sleep in? Any ideas where to get them?