Given your apparent expertise with this building, is there any chance you could create a hole in the floor to allow two steps down and back up to get under a section of the layout without much ducking? The opposite approach would be to create ceiling height for stairs up and over and perhaps a viewing platform.
My layout is smaller, 8 x 19. It has lots of switches, buildings, moving stuff. I can with some patience move a train from the most outer 4th loop to an inner 3rd. Inner most loop dedicated dog bone. Outer 2 loops have elevated sections. Great fun! But it is all O gauge. My desire is to re-do it removing some O, adding some standard gauge and maybe an OO loop. My reason is that my enjoyment comes from restoration and repair more than operating these old pre- and post- war marvels. No real advice other than to enjoy your trains.
