rkassi,
I winter in Ariz. 4 months a year from Dec. to April. My friends from Mich. Wisconsin leave in Oct. Nov. to avoid the winter/snow/storms/road conditions. Because of so many "snow Birders" from back east and Canada who are heading to warm weather areas, my suggestion is make your resevations well in advance. In Ariz. I make my reservations in April for the next year. It depends on what type of RV Resort/Park you prefer. If you don't need many amenities, advance reservations is less of an issue.
Just a plan to deviate from, I would make a list of areas, towns you tenative plan on taking when you leave Wisconsin. Then go on line to the Good Sam TL Directory web site which will give a list of all the RV parks and their facilities and make your choice. I prefer to have a reservations a couple of days in advance of my arrival, you can always cancel so you are not locked in to a schedule and will maintain your sense of freedom. Personally, all the states you mentioned with the exception of Texas are states I have enjoyed visiting. Not to offend any one Texas, Texas was just a lot of long open roads and it took 2-3 days just to get across the state. I also had the misfortune to get caught in a hail storm---- $25K damage to both my trailer and truck:(. The ocean coast of Texas was the good part of the trip. I especially enjoyed New Orleans, Disneyland for Adults:)