Here I made 2 small and a bit sloppy edits to show what I think would be a good direction as far as detail goes.
I think the strong planes are very nice, you do not need to have detail everywhere, especially not nondescript detail.
Add stuff like breaks and such and make sure the moving units read well infront of them.
If you do colour tints try and have them make sense. That green you have on the exposed concrete does not look nice imo.
For the background trash kinda stuff I would do 2 or 3 colours, all very dark and subtle and then do some general junk and some detailed bits and bobs sticking out here and there.
I have to say I like tho what you have so far, just not the texture on the latest stuff.