Wool and overalls works for me. I like the overalls because when I'm walking in I can zip the front down and they vent well, keeps me from overheating and sweating.
My experience is if you have a good pair of boots, you keep your middle warm (kidneys), your head and neck covered, your good until it gets pee freezing cold.

One of the better layers I've found is German tanker coverall liner (surplus). Synthetic, over your long Johns and layer from there. Lightweight, synthetic, dries really fast and just works for me. And the price is right.

Kind of a person to person type thing, some people are less tolerant than others. I don't require toasty warm extreme comfort. And it has to be very cold and windy before my feet and hands give me any real issues. One tip is to eat well, I usually pig out on pasta beforehand, I feed that furnace.

The wind is your cold weather enemy, a good plastic poncho can be nice in the short term, Either over your clothes or to make a quick windbreak. Anything that traps moisture can cause issues though, better if what you are wearing breaths.
I'm partial to old school wool army blankets. I sewed two together on two sides, long side and short side, it makes a quick, durable, cheap and easy blanket. Burrito. I either wear it like a sleeping bag with my feet in the closed short side, but I also left a head sized gap on the short side so I can also wear it as a cape. It doesn't have to look pretty, but t does have to work.