Thats one freaky looking alien City/Weapon platform
.
I just figured out what was missing form your pics: Damaged, retreating ships and burning hulks.
The battles seem too clean, with no rubble.
Maybe some smoldering bunkers, or burnt out tanks, or a crashed fighter sticking out of a hill.
PS: How can you take over a gas giant planet with
tanks?
It's probably not important enough to redo all your troop images, but just something amusing to think about.