I travel the routes frequently and am always pulling off to take a picture or just look at stuff. I would suggest going south...down...thru the Fraser Canyon, #1. There are lots and lots of pull-offs, all on the river side. That's your right, going south. Once you get past Lyton the rivers on your left but pulling-off is still no sweat. This isn't the high volume road it used to be. Trucks and so on, but the volume isn't there.
The Coquihalla (The Coke), #5...meh...there isn't a lot to see no matter which way you are going, and when there are, you'll find pull-offs.
Gary Haupt