Liners - For hiking and mountaineering I always wear them. They help with wicking and can reduce friction, leading to less blisters if you have hotspots on your foot. I use silk liners, and you can pick them up at your local REI for about $7 a pair, if I remember correctly.

Wool hose - Here I'm a bit confused. How much of your concern is aesthetics vs. function? I go for all function, and I only use SmartWool. Bar-none, the best sock for your hiking, mountaineering, and skiing needs.