Can’t even remember the number of times that I asked people to organize their BG setup properly for compositing, I even had to clean them up after finding a lot of trashy layers. Well someone ( this amazing guide and it’s a must for any production regarding the size.

For added context: this is the BG design used in the 2nd and 3rd image, so you can see the whole composite
Extra: Using smart objects to easily edit/paint multiple instances of the same object in a scene all at the same time. Or: working smarter not harder
Example: This BG has only about 5-6 different trees total, free transformed / flipped to create variation. As smart objects the total work is reduced and it doesn’t cost me much effort to make it this way in the design stage.

All credits go to: