I term photo scenery as "fly over" scenery. From takeoff to flight level, generally 1,000' and then from flight level to landing I'm not worried about the "flatness", as flying the plane takes priority over the visuals.
Autogen might be nice to have, but people don't appreciate the work involved, especially in a large scale project. I have a couple of payware addons for some islands sitting out in the Pacific, think Aloha! Autogen was added, but IMO doesn't really do much to enhance things. The developer could have spent the time removing clouds out of the imagery, rather than placing about 100 trees here and there.
Another consideration with autogen and photo work is that autogen takes rendering priority over textures. There's only so much that can be done in the rendering loop of FSX. If autogen is taking rendering cycles, that leaves less time for drawing in the sharpest texture level. I'd rather have sharp textures than a few oversized trees and buildings, that once at flight level do little to nothing for me.