Glad to see that you are finally ready to leave Texas and explore the beauty of Canada/Alaska.
Be aware that the Canadian border people are very unfriendly when it comes to bringing in more than a liter of hootch! Yes, Liquor is expensive in Canada, but not as much as getting your motorhome totally torn apart and then fined for any overage. (Been there, done that.)
Yes, go up through Idaho, see western Alberta, Jasper Nat'l Park, etc, then wander over to the Alaska hwy. Be sure to stop at Watson Lake and view the Sign Post Forest. (You will find several RVAers have left their signs there). Take you time in both Canada and Alaska.
On the way back down, take the western route through BC and come down the Cassiar hwy.
One thing Linda did before we ever left home--go on the Internet and get all the Alaska travel itineraries fom the various RV caravan people (FMCA, Adventure, Fantasy, etc). Look at all of them to see where "all" the tours go (good things to see), but then look at their schedules and plan to be somewhere else when they are in a particular city or campground.
We spent 2 1/2 months in BC alone, and we loved it!
Enjoy your trip.