L-shaped layout builders, arise!
There are some inherent advantages to an L-shape; avoiding the rectangular shape that often tends to breed concentric ovals, opening a future option to transform the "L" into a "E" or "Z" pattern, and using one leg of the "L" primary as a classification yard. For this project the available space was an L-shaped addition (formerly a home office) to our house, so that space dictated an "L" layout.
Attached is a JPG of the L-shaped layout I'm now working on. It is the lower level (the upper level is a work in progress) with O-gauge Lionel tubular track, O42 curves and O42 K-Line switches. Unfortunately, the PC-based track planning software I'm using (ANYRAIL) does not provide an image of a 60-degree crossing for installation at the center of the layout. I'm still working out the geometry for that crossing, which is a key element in reversing loops.
Carry on ...
Mike