The example image only shows some of the ridiculously fine details I'm agonizing over. I plan to do the tree trunks in a completely different way which means the more screens I make beforehand, then the more screens I'll be redoing later. Either way, I'll be tweaking tilesets and adjusting screens up till the end. That's inevitable.
Also, now that I've made KS+ I can free up a ton of space on the dirt tunnels sets. That will allow me to do a lot more with those screens.