personally, i wear a baselayer and a thin windproof as i get hot quickly, my warm kit of which there is plenty lives in my pack in case its needed. a wise man once told me to start cold and it seems to work for me, a couple weeks ago in Germany i was at -10 in a helly hansen lifa and a windproof, the activity kept me warm, my pack would keep me warm if i had to repain static.
This - I'm exactly the same. Buff on the head and a thin pair of gloves if need be. When you stop and start to cool down, then you layer up.