Where to start?

[RogerB]

So, you have an “out & back” or shunting layout in mind?
Am I right in thinking the white rectangle is an access point?
I don’t see any major issues there all sidings are accessible on return and the top line [Northernmost on the plan] is level, I assume, and doesn’t traverse the incline but goes directly over to the sidings on the right hand side?
Will the length of train you might run fit in the sidings at both ends of the run?
R-