I am goingto be getting a couple sets of the merino wool longjohns, probably not in time for this yr, but next for sure. First Lite stuff gets awesome reviews, although it is expensive.
The advantage to the Merino wool over polypro is smell. The polypro gets pretty ripe, such as the UnderArmor and the military stuff I use. Wools does not do that,and the elk hunters who do a lot of back country trips swear by it.
For wind resistant layering, I have a set of the Cabelas packable rain gear. Its their Dry-plus stuff, very light weight and packs into a little stuff sack the size of a beer can. I wear it as a layer under my outer clothing, as it does a great job not only beating the icy wind, but works well to contain your scent too. Its thin enough that it doesnt bulk you up.