Dual chargers are nice if you plan to use anything over 40amps. (Note: Dual chargers will give you up to 80a charging.)
If you're "crossing a charger desert", try to plan your trip so you spend the night somewhere in the "desert". This is the easiest way get through remote areas because waiting around in a remote RV park for a NEMA 14-50 plug is neither fast or very fun.
If you've got a route where you need 2 charge stops to get between Superchargers, either consider a different route, or plan for something to do while you're waiting. I note if you go up to Coeur d' Alene in Northern ID, you can drive north on Hwy 95 to Creston, where there's a Tesla HPWC (doesn't give the amperage, maybe you can call them and find out). From there, you might get a meal while you add range, and the spend the night somewhere between there and the Revelstoke Supercharger.
Best thing to do is call ahead as you're making these plans. Plugshare doesn't always have the current or correct information. If an RV park is open, make sure they have "50 amp hookups". RV parks don't really understand the time impact that a 30 amp outlet has for us compared to a 50 amp outlet (the 30 amp outlet is 120v at RV parks, the 50amp outlet is a 240v NEMA 14-50). There are way more RV parks than what shows up in Plugshare. Again, call ahead and find out before you drive out there and discover their closed, or their 50amp services are actually rented to long-term tenants.
If it were me, I'd add a day and drive further west and aim for the Hwy 97 corridor in Canada. Lots of SCs along there, and I'd enjoy the drive through the mountains. I'd SC in Coeur d' Alene, Idaho, head north to Creston, top up there while eating dinner, and then spend the night somewhere along Canada Hwy 3 heading west. Next day, drive to Penticton where there's a ChaDeMo charger, or if you can make it, Kelowna Supercharger (depending on where you spend the night and if you can fully charge overnight). Then you're back on the SC network all the way to Calgary.
There seems to be lots of charging options along Hwy 3 along the border. For something like this, do whatever you can to get your car is plugged in every moment its not driving you down the road. Stop for lunch? Do it where there's a charger. Spend the night? Make sure you can plug in and end up with a full charge the next morning.