my many years of wearing wool (and softshells) as much as possible now, after being seduced by the first versions of HH polypro and Patagonia Capilene (and goretex stormshells mentality of the 1980s') is the exact opposite of atonkelly:

wool is the ONLY base layer that keeps you warm once once you've stopped and does the best at avoiding the sudden convective chill out so common in wetted out synthetic base layers.

as to the outer layer: less waterproof, more breathable in the outer layer. windshell for riding not a rain jacket shell.

Experience for me time and time again, on ski patrols on Mount Rainier and mountain rescues across the pacific northwest, (and winter season bike tours, of course) was that WOOL kept me warm once stopped in stop and go exertion activities in extreme cold. My fellow patrollers, once stopped, would suffer tremendously from the chilling effects of wetted out synthetic base layers. its very tough to get a saturated base layer in wool unless you fall into a river.

pack a synthetic puffy vest, and wool vest ( I use a cashmere one from a thrift store) and silicone nylon vest. these are very valuable in the layering strategy. as an outer shell, a MEC supermicrofit cycling jacket is pretty much ideal for cold weather touring on the bike.

off the bike, a big, primaloft jacket, and puffy booties. small foam 'sit' pads to sit on and stand on and an extra foam pad to sleep on.