Well, so I was able to create two routes of O-48 minimum curves and turnouts! Lionel does make a few things needing O-42 minimum, so O-48 obviously covers that. Plus trains just look better (and run better) on wider curves.
- This route is return-loop to return-loop. I widened the upper loop to O-48 minimum. The bottom large return loop the outer track is now all O-48 or better.
- With the addition of Lionel's Extended Truss Bridge as a lift-out bridge, the outer oval is also O-48 minimum. Certainly, the door has to be position correctly (or remodeled) to match up with the 30" aisle.
This layout concept has certainly evolved to a respectable track plan, a plan worth having and running trains on 
. I particularly like the multiple routes, that keeps things interesting when running trains. And I don't mind the common single track/upper-loop, as having trains stop at a block signal and wait for a passing train is very cool "in the wild", and cool on a layout.
