Narrow gauge model railroading
Maybe dark isn't the answer
Originally I had planned that the entire project be quite dark. The hypothetical location was to be in a fictitious mountain range, where it rained a lot and the earth didn't always dry out. There was to be a lot of pine trees and my models mainly freelanced, with a few based on some Denver, South Park and Pacific stuff.
Before doing the dark thing to the whole layout, I put together a little diorama to see how it would look.
This is just an idea and so a lot of small details were not added.
It's too dark, so will rethink (yet again) and try to come up with something else.