What to do here ?

[Tom]

I like the idea of a narrow gauge line up top. Assuming (yeah, I am guilty of that too from time to time) you are building this in HO, an HOn3 line up there would be cool. I'd go up from there with mountain scenery and tall trees. Maybe a Sawmill at the far left that is 2 story perhaps, served by both the narrow gauge (raw lumber, logs) and the standard gauge below (finished lumber).