I use hiking pants quite a lot. They are not waterproof, but at least somewhat water repelling and they dry out really fast if they get wet. They also protect well against wind and are wide enough to use long underwear beneath if needed. Don't look very stylish, but that I don't care about.
My standard go-to setup for winter walking is
- trail running shoes or running shoes with spikes if icy. Wool socks. Shoes waterproof.
- hiking pants, long underwear if very cold, but generally not needed.
- merino wool base layer, a thin fleece if very cold
- a thin gore-tex shell jacket with hood
- a woolen hat
- gloves, windproof and/or waterproof
- a small backpack with extra clothing if something gets wet / have to stand still. Generally includes a thin down jacket and a more heavy-duty shell jacket,
Outdooor clothing is one of very few areas in life where I'm willing to spend serious money. Staying dry and warm is key. If its very cold there isn't really much risk of getting wet but keeping the wind out becomes even more important.
For shell clothing I've used Arc'Teryx for the last 20 years. Pricy, but great stuff. I have a pair of waterproof SealSkinz gloves I really like, my Asics Fujisetu has served me well for many years, not that often I need the spikes so they don't get a lot of mileage every winter.
For running I use same footwear, tights, shorts (the senistive area can get pretty cold), a thin merino wool shirt, gloves, a thin hat and a windproof running jacket. That's fine down to -15C/5F for me at least.
If you're not freezing a bit the first few minutes you are wearing too much imo. Im always surprised by how much clothing some put on when the plan is to be on the move. After a few minutes they start sweating and have to stop to take off something. Anyways as always layers is the key so it's easy to adjust up or down if needed. Thick, bulky coats are for standing still. A thin down jacket used as a layer beneath a shell is surprisingly warm, lightwegiht and comfy to wear. My favorite is the Arc'Teryx Atom LT which isn't really a down jacket but warm, compresses well and lightweight.
If I know I will be standing still to watch some kid's activity or whatever its a big-ass jacket bit like Canada Goose and Sorel Boots. Those are awsome.