Nice photos. You're giving a better overview of your layout. I think I may have you on the age of a layout, I am currently passing 30 years on mine, and still have a few areas where the plywood is still visible. Unfortunately, my layout sat more or less dormant for a number of years because we have no hobby shops at all in our area. Internet retailers weren't around yeat and about the only time I could actually see a product in person is when we were on road trips. If I found a hobby shop, my wife's eyes would just roll around.
I really like what I'm seeing on your layout. I don't have any chouce on my main line as the tracks only go through any scene one time. It was built as a point to point, but I can run continuously with the use of some hidden staging tracks. What I'll do is after a local freight trains brings cars to one of the two yards, an outbound train will be made up and sent "off stage" to the hidden staging tracks where it will later become an inbound train.
Enjoyed the photos. Thanks for posting.