Most of my cycling clothes are wool, because it's awesome. This time of year you need an outer layer for the wind (and rain), but all my base layers & shirts are wool. My mid layers are goat wool. All my socks are wool. So is my hat. And my gloves.

Use a 150 grams per square meter base layer at 40 F, and a wind blocker over it. Maybe something in between for insulation if you get cold.