Otherwise, you'll be fine.
I'm over there about 10 times per year and have spent time in London and Glasgow. I don't suspect the drive will be all that enjoyable but it is what you make of it.
It will be dark by 3:30-4:00 p.m. in the height of winter and will start getting light at around 8:00 a.m. Winters are usually mild but can be snowy and travel can be pretty hazardous if you hit a snowy/icy spell.
There’s lots of traffic since Great Britain is densely populated and the roads can be very congested especially around the many cities.
That said, it is a beautiful island and you can have spectacular days in the winter. If you get a chance, get out and walk — so much to see. It is almost always comfortable to be outside if you dress appropriately (same can’t be said for much of the US)