Sorry for the late post to this thread, but I just went through old emails, and saw a forum digest dated from Feb 13 that I never read. I have followed your other posts regarding vintage Lionel accessories, and we seem to have similar interests. Thought you might be interested in my "dream layout" still under construction that is designed to have grandkids operate as many accessories and motorized units (slowly adding LC+ units) as possible. Here are descriptions of the numbered photos attached.
First to your comment about an experimental layout. I began mine about nearly 5 years ago. Photo 1 shows the general plan in Feb of 2016. Consisted of a temporary table top of styrofoam sheets on tables and work horses. I knew there would be an around-the-room double-track passenger mainlines on the upper level, with a single track main line on the main level and lots of spurs for accessories and various freight road names important to me. I added a 3rd level for the rocket launcher, with a spur that will appear to continue into a mountain tunnel. The intention was to have grandkids operate accessories from the ledge on stools, as well as other accessories from inside the room that require my supervision/assistance (milk and cattle cars).
Photo 2 shows a closer view. Note passenger station in background on left and milk/cattle cars at top of inner area.
Photo 3 shows current status. It is a panoramic shot so the ledge is distorted and looks curved - it's not. Backgrounds (intend to have 4 seasons) and permanent bench work added. Also shows that I decided to move the passenger station (will create one long platform) along the ledge and the milk/cattle cars on a spur and in a different area to allow me to be at the top of the inner opening to operate the controls. Gets a bit tight with the grandkids inside. Photo 4 shows the location of these and other accessories. You can see classical ones: magnetic cranes, coal ramp and loader, bascule bridge (that's a newer version to replace the original that finally gave out), yard man, log loaders (164 and 364), and sawmill. Blue paper represents harbor I will create.
Photon 5 shows that I wanted to add some fun and fantasy to the layout...why not?? It begins with a log dump into the 164 log loader, then logs roll down a ramp to the sawmill (get about 75% of them in the bin!), then I place them on the 364 log loader to return to logging area, where someone else picks them up and returns them to log dump car to repeat the process. The photo also shows the control box for the rocket launcher on the ledge. The grandkids fire the rocket and other "people" into space, but I retrieve them. Don't want the kids firing them without supervision. There are also lots of other buttons around the layout to operate other units: ice skaters, sound modules, Moe and Joe lumber car, lumber jacks, etc.
Last photo shows the hinged access for me to avoid bending and head butting to access in the inner area. I followed the method described by Jim Barrett in OGR Magazine and it works like a charm.
So to your question about a shelf-style layout to accommodate those accessories, it can certainly work! I have spurs that either go nowhere, or are connected to the main line and have operating cars that just sit there. Starting with an experimental layout is best. In tight quarters, tolerances are critical, so took me some time to make everything fit. Also be sure you have good access to remove and maintain those vintage accessories. They need constant attention.
I have finally reached the point where most everything works...today, at least. My next major phase is scenery. That's my least experienced area, but have lots of resources and eager to experiment to learn how to do it.
Hope this helps Have fun!