A full chapter in a book and several articles on the subject were read and the information absorbed. The most useful suggestions learned were to build it for the primary operators and to test deck heights and scene depths with the use of mock-ups.
As discussed before, this layout has six separate modeled locations that are operated one at a time before moving onto the next. The layout not being the walk along follow the train type makes it practical to operate the three lower scenes while seated and the three upper while standing. The lack of enough layout floor space to have two large staging yards at a practical height necessitated that they be built at an elevated location. These highest levels only have to be worked before any operating session.
The Mock-up therefore was easy. The average eye heights of the two primary household operators were measured from the floor while sitting on a computer task chair, standing on the floor and standing on a 2' stepladder.
These photos taken early in the construction demonstrate the layout heights.
Considerably more photogenic than primary operator #1, primary operator #2 demonstrates one of the seated level locations. The three seated locations are desk height at 31" - 34". Scene depths are no problem at around 2'. The shallow depth intermediate staging above can be operated either seated or standing. Plenty of leg room under the lower level and when chair is pushed under out of the way, the top of the back of the chair does not exceed the deck height.
This is not a big layout, the longest scenes are 18'. Scooting right or left on a rolling chair to work the lower levels is easy.
Standing level locations are at 54" - 60", Again shallow intermediate staging levels can be operated both standing or seated. Standing location Danbury shown here is 40" deep, but accessible for cleaning the deepest track from a short stepladder. The other two standing locations have a scene depth of only 2'.
Top level staging at 75"-79" is worked from a 2' tall step up aluminum work platform with a secure 1'x3' standing area, this safely replaces the stepladder in the below photo. The work platform slides under the lower level when not in use. Grab handles will be attached to the front edge of the upper staging deck every 16" along the length of this deck to assist operators ascending/descending the work platform. Threaded rods attached to the floor joist above ceiling support the upper deck and the added weight of the operators when using the grabs.
A more recent Photo of the same area shows how this has worked out. The defined edges of the locations/scenes are now apparent with some of the fascia installed.