Thanks for all the suggestions. It may be that it just takes more experience. Where I live isn't very bike-friendly from a road/traffic point of view. I've experimented with a number of routes over the years to avoid narrower streets with a lot of traffic, taking me onto the sort of back streets that don't get plowed quickly. Great when the roads are clear, but maybe not so great when contending with snow.
I've been a 9-month bike commuter for years. (Which really means I would bike in any month provided there wasn't snow or ice, but as a practical matter that meant I biked very little January - March). I hoped to extend that a little bit this year. I'll have to see how it goes. The studded tires will definitely help get me out there when road conditions are pretty good, but there are the occasional patches of snow or ice).