It's hard to imagine just how far apart everything is there after living in the UK.FellPipe, the U.S. has a lot of territory, so it is likely best to plan carefully and visit selectively, using air travel and rental cars. Driving takes too much time, unless you are an ardent driver, and even so. I'd pick maybe three urban centers, and strategically placed small town and rural areas probably including National Parks. You can see a lot in a week or two, if well planned.
I am an avid motorbike rider though so the dream is to get on a bike and explore, hopefully taking 2 or 3 months.
Not something that is possible for me until retirement but definitely one of the first things I will do after.
I have friends who I will hopefully visit there soon though, once civid restrictions are finally lifted.
So I'll be able to stock up on some of your fine sounding tobaccos and do some small scale sight seeing.
30 more years until I can do the bike trip of a life time though... I hope motorbikes are still allowed by then.