How long do you have to make this trip?
One piece of advice. Stay off the interstate highways. You will see much more of the local flavor if you do.
Are you zigzagging around or driving "straight"? Because if you go straight there is no way to not miss things. But there are places to see all over though some regions are more densely packed than others. Distances here can be vast in comparison to those in Europe.
The US does not have the density of things to see or the depth of history as in Europe or Asia. Much of what there is here is the landscape, the national parks, etc. And the people can be lovely. Engage them. I come from a European family but do a lot of business in the rest of the country and I have found Americans can be very friendly and honest. They can have a lot of preconceptions, but the truth is so do people from other countries.
Read food blogs or check out the show (or their website) of "Diners, Drive-ins and Dives" for some good local food all around the country.
Good stuff, thanks!
Our trip will last for 4 weeks. We have created a shared google maps and there is a lot of pins regarding those national parks. Mostly they are near west coast.
Everyone seems to emphasize the meaning of food places. I need to add some pins to our route based on the stuff I find on internet.
-EDIT- And yes, if our route is drawn on a map, we will do some zigzagging atleast.