It must be bred into us, but I have never really thought of the Hwy1 winter drive as anything extreme, just your normal PITA winter driving.
Bring windshield washer fluid, you will use it. It sux real big to be out of it halfway between towns.
If there is a big storm cycle, it is quite possible that Roger's Pass will close.
Don't be in a hurry. Give yourself lots of time, so you don't feel the need to push it. Stop at the Interpreative centre at Roger's Pass. It's cool.
Budget for the possibility of needing a new windshield... might be time to upgrade your insurance.
If end up going through Spokane, then bring your tele skis and look me up, I'll be in the BC Kootenays, and like to show people around.