I'm constructing Basement Layout 2.0 and am pondering where to place some of the classic postwar operating accessories. I'm not referring to lighted buildings or even trackside accessories (gateman, semaphores). I'm specifically referring to things like the crane, coaling station, operating water tower, unloading platforms for milk and merchandise cars, operating mailman cars, and the vibrating cattle car. I think that covers my inventory of accessories.
In Layout 1.0, I had these in a "yard" that was more for storage and accessories than an operating yard for building and unbuilding trains. Layout 2.0 has a real yard so I don't think these accessories belong there.
So, assuming they don't go in the yard, I'm mainly I'm asking about the pros and cons of putting them along a mainline or an "industrial spur" off the mainline. On a mainline means trains have to stop which creates some activity for the operators but interrupts flow. On a spur, especially thinking in the future with grandchildren, they can play with the accessories without interrupting the flow AND it provides an activity to drop off the cars for unloading.
Would appreciate any thoughts based on your experiences.