Of the few times I've driven long cross-countries like that, the only planning involved is the route to take. I don't plan the stops because I have no idea when that will be. I did California to Wisconsin a couple of years ago and was able to do two 700 mile days in a row. I left late the first day and only did a couple of hundred miles. Then did the two 700 mile days and then the last day was only about 200 miles to finish it off. When I started the trip I would not have guessed I could last 700 miles driving but the motorhome is so comfortable that I did it just fine.