This is what I would do and have done.
Tucson to Banning CA KOA for the night
Banning to Jalama Beach County Park two nights
Moss Landing KOA 2 nights with whale watching the second day
Moss Landing to Willits CA KOA overnight
Willits to Oceanside Beach Front RV Resort Charleston OR two nights
Oceanside to Collier Memorial State Park two nights with Crater Lake on the second day
Collier to Reno NV overnight
Reno to Kingman AZ overnight
Kingman to Tucson
If you have the time add a two nights at Lake Tahoe instead of overnight in Reno.