I would think you have come to realize there are lots of options. It would probably be better to narrow those possibilities down to what you would like best to see, do, and/or experience. I live in southeast Arizona so Springtime, with trees turning green and the flowers blooming would draw me to the Southern states. And the history of that area is another attraction. However for scenery, geology and ancient history you can't beat Arizona and Utah. Of course both these regions are loaded with super campgrounds in national forests and grasslands.