Migflanker,
The last time I flew from SFO to CLT I had my atlas. I was able to see several National parks, including Bryce and Zion. It was clear enough that I traced the interstates all the way to Georgia where it became cloudy.
I love flying over the big Mississippi, it always gives me a thrill to match up a city with the atlas.
I see that most are west coast based. I would add flying over the Great Lakes. Up the east coast from Florida to Boston, picking out all the main cities from DCA, BWI, PHL, NYC and finally the Capes of Mass.
My most favorite window flight is one on the evening of July 4th. Every little town has fireworks. Plus the upside down view has a beauty of its own.