More to add later but here is a real time example of track planning.
The picture below shows two plans, both based on 5M by 600mm. It is supposed to be a VR shunting layout. Micro Engineering track and Shinohara points are planned. It is to take all kinds of VR steam trains.
These plans were done on paper, then scanned in and altered. They ar enot strictly to scale, though the red 1ft gris is still visiable.
The top plan is plan "A", the bottom is Plan "B"
This is what I call a more traditional design. It has the the staging yards behind a low backscene with 2 tracks, taking a trains about 4ft long. The station the train goes into is about the same.
Plenty to shunt, and the seperate loco depot is extensice enough. It is bigger than the "station" would have, but it is one of the main focus of the design. Let's call it a small branch to a bigger station "off stage".
Scenery wise we have a bridge breaking the scenes into two, and helping hide the entrance to the staging yard.
Operations wise you could have trains comming & going, plus lots of locos. The layout allows the train to depart and dissapear to somewhere.
Plan "B"
This design has visable staging, in that one end is effectively staging. In this case the mainline in front of the loco. But that depend s on what side you are working from. Since the loco is that much higher, it will hide the trains to a degree if looking from the other side. the design also allows for expansion.
It is a double track mainline with a island station, some yards, and the loco depot up a hill. This gives more than one level, a slight grade, and is more about the depot as the main feature, this one could have that engine shed.
Once again I have a bridge breaking the scene. The yards are complex enough to keep a shunter happy.
This is the better one I think.
Remember these are just concepts, buiding etc subject to change as one see's fit!