Jim,
You said you just retired. My first advise is that you need to get into retirement mode and Sloooow down. Don't try to see the whole country in one trip. We are based in the Mid-Atlantic East Coast and travel to visit family in Arizona. It takes us 12 travel days (@ about 250 miles/day) each way. We do not travel every day often stopping and staying as we find interesting places along the way. My suggestion is to break your wish list of states into geographical regions and then spend 3-4 months in each group of states. Last fall, we spent over a month in New Mexico alone traveling a loop of about 1,000 miles through various parts of the state. We have found so may great places in our travels over the past 10 years that I would not know which two in any state to pick, especially without knowing your interests and proposed route.
Here is a list of links that I use when starting to plan a trip to a new area:
National Parks,
National Wildlife Rufuges,
State Parks,
Scenic Byways,
National Historic Trails,
Legends of America,
Trip Advisor,
Roadside America,
Ghost Towns,
Slot Canyons,
Pow Wows,
Flea Markets,
Rock Art,
Native American Ruins,
Factory Tours,
Waterfalls,
Scenic Railroads,
State Fairs,
Lighthouses,
Breweries in the United StatesWineries in the United StatesHope you enjoy retirement and have a great trip wherever you choose to go!!