Make reservations now for RV Parks near Glacier and Yellowstone west entrances. Suggest North American in Coram, MT and Grizzly in West Yellowstone. Then Coulter Bay in Grand Tetons. The Highway to the Sun road in Glacier may not open until July 1. Yellowstone is best for wildlife before all the tourists drive them to the higher elevations.
Other than that, try to have a general plan but do not force yourself to follow a tightly defined schedule. We found it best to travel no more than 200 miles, then stay a week for better rates and sightseeing with the toad. Think of yourselves as nomads, wandering from place to place while on a protracted journey.
California is very expensive and we blew thru there, from south to north, before school was out for the summer. North to south is better for pullouts, but your 40' plus toad will not be a good idea on some sections of Hwy 1, or Hwy 101, for that matter. Oregon coast is long and breathtaking. Best places in California were Avenue of the Giants (Ancient Redwoods RV Park) , taking the Jetcat ferry from Vallejo to Fishermens wharf, going over the Golden Gate with the motorhome, and the thousands of elephant seals on Piedras Blancas beach near San Simeon. We skipped the Hearst Castle tour and never made it to Yosemite. Maybe next time, along with the north rim of the Grand Canyon and all of Utah.
PS - Use a trucker's atlas to make sure your navigator doesn't send you on some road that you should not be on. Ask me how I know this.