Here, a typical winter day is, like, high thirties to upper forties and raining in the way it does up here. Which is to say, more of a hard sprinkle than a serious Texas rain. When that is the situation, I have on thermal/fleece long sleeve jersey and bibs/tights. No base layer because I will get too hot. Merino socks. Helmet, no cap. Ten year-old Novara rain jacket over the jersey. Some North Face gloves that work great, even though they are not for cycling. That's it. I am buying the Velotoze Tall Shoe Covers this season, but I don't have experience with them yet.
If it is dry and really cold for us (20s or teens), I will add a base layer top and bottom of el cheapo stuff from Target. A Proviz vest over the jersey. It's more than enough for me. If it is snowing or if the temp. is hovering around freezing while raining, I usually do not go out. We don't get a lot of snow here, but we do get ice and I have one big spill on it already.