Yes we use provincial parks but before school gets out end June or after Labour Day. Can't get near those places in the summer when school is out. They do have a reservation system but you have to book really early. Wouldn't work for us, where we like to be wandering along without a tight schedule.
Suggest the Can/Alaska forum for tips on all that side of things.
Honda is behind the cab. I have tried charging loose batteries in the truck bed from a portable charger on the Honda. Works. Not tried it with an extension cord back to the trailer with the charger back there on the installed batteries (or instead to the shore power cord to run the converter) but see no big deal there if you can keep the cords off the ground.