I agree with the others. The two major holes I see are: 1. The Pacific coast from San Francisco to Portland. The section between L.A. and San Francisco is somewhat similar, but there are a lot more lighthouses up north. I don't think you should sacrifice seeing the Sierra Nevada though. Maybe cut over from the Pacific to Sierra around San Francisco, then rejoin the coast in southern Oregon? Then over to Wyoming. 2. Southern and Central Colorado. Mesa Verde and Rocky Mountain NP are both great. Mesa Verde is a cultural site with cliff dwellings. Rocky Mtn could be skipped if you've seen mountains elsewhere. Maybe see Utah/Colorado after Glacier NP? Any interest in Key West Florida? It's really just a long bridge out into the Caribbean that leads to a tropical tourist spot, but a lot of people want to see it.