Jim - about the original Lionel accessories. Sure, a good number of the original accessories can fit in, but I have not made a study of it. There is more space to widen the yard to fit accessories between the tracks as needed. The small hill above the Menard's station (which is huge compared to the original Lionel accessories) can be deleted for more structures (as can the Menard's station). So yes, I think that nearly all of the original accessories could be made to fit, if that is the desire.
I had in mind the idea of pulling the layout into a more sustainable (sustaining the operator's interest) track plan with more operation options and interest using modern ideas about track planning (like the O-48 loop, many O-60 turnouts, the moderated grade to 4%, reverse loops, separated main lines with cross-overs, better access), and bringing the terrain and structures into a more modern look. But there is no reason why the plan could not stay with the original vision of a flat table-top with accessories - more like a Lionel display layout look. That also is a very cool and attractive look/design.
I think the original assumed that there would be 360-degree access all around the layout. Making the 9X14 plan needing like a 14X20 space. Few folks have that kind of space, and if they do, would want to look at alternative track plans like around-the-room and other ideas. So access is a consideration when the layout will have to be up against a wall or in a corner for most of us. The tilted version needs 11X16 space including the aisles, and provides pretty good access, just one spot hard to reach.
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