I would also look at these websites/apps to help with the plotting of places to stay.
1. Good Sams. Has a wide array of info on the website (app sucks). Lots of info along plotted routes. Things to do, festivals, history, etc. Campground info is okay - but isn't as extensive. Also doesn't show Walmarts, Camping World and other free overnight stops.
2. Allstays. Downloadable app is very good for finding places to stay. Lots of filters that can help find free stays.
3. RVParkReviews (RV Park Reviews - Trusted Reviews of Campgrounds & RV Parks
). Great info direct from users.
My method for finding a good, clean, well maintained and safe campsite.
1. Plot the route with Good Sams
2. Locate places to stay and stuff to see.
3. Validate places to stay with Allstays and RVParkReview.com.
4. GasBuddy. Not sure of your vehicle/RV but planning with GasBuddy to find the lowest price gas along your route will save you hundreds of $ - literally. With a V10 and 80 gals of gas, I can plan my fill ups to find fuel that is the least possible. Take a look at fuel along your route. HUGE.
Prior planning makes the trip easy to do. Plan,Plan, Plan