My commute is an amazing 2 km right now so my experience of the matter is limited. I just thought I'd throw something in:

Make sure you have what it takes to change a flat in the dark. Obviously, it would be more pleasant and faster to have a spare tube instead of patching, and to have CO2 (AND a pump as a backup) and to know how to use it, and to use it fast. And a headlamp to do the work.

That's somewhat obvious. But one of the reason why I don't ride much in the winter time is that I hate changing a flat on a wet, cold wheel with wet, cold hands.