In response to the comment on your thread, I think I have the wiring problem figured out, but we will see once I'm actually up and running!
Access would somewhat be an issue. I thought about making two removable cutouts inside each radius (blue and yellow circles), but I think what I could do is in the red triangle-like figure in the picture shown below.
I'm not too sure what I'm going to do at the door, I may make it a hatch-type opening, I'll work on that once I get to that part.
I'll probably only have one industrial-like area near the yard and single track on the right of the red triangle. My plan for that track is actually a single stall engine house. All other open areas I want to make a town. My largest engine is a Railking Allegheny measuring about 27 inches with the tender included. Then longest cars I will be using are the Husky Stacks which I believe are 17 inches (cant remember though).
As far as the buildings.... I have Ethyl's Gas station and O'Grady's Tavern, BUT... I think I'm actually going to try and make all of my own.