You picked a good one, we used to do a loop on the bike. We would alternate between WA 20 and our Crowsnest Hwy along the bottom of BC.
There is one fairly steep grade just east of Concrete, but it's not as bad as some of the grades we've drive in CO.
A little bit of trivia, some the 1998 Kevin Costner box office smash hit, The Postman, was shot in the same area.
When I was a kid I was going nowhere fast, now I'm an old man I'm going everywhere slow.