Oh, my friend, you have bitten off quite a big bite there. The west alone has enough "must sees" to keep you busy for years, and it you throw in the east and points in between as well, you are going to need decades at the rate most folks cross them off the list. Others have mentioned a bunch of places, I'll add a few more: Zion, Bryce, Death Valley, Glacier, heck, you can't go wrong with almost any of the National Parks.
Shenandoah NP in fall color season, Acadia, Charleston SC (stay at the Charles City County Park, it's incredible), the Smithsonian Air and Space Museum at Dulles Airport. Williamsburg, VA. All over the Upper Peninsula of Michigan. I could go on and on.