Dave, thank you for finishing off the "double track" plan. At this point, I do not think I want to go that route. I like my collection of photographs like the one JD just posted above. There will be a big curve in the corner and some flex track can make for some slight curves to give a hint of winding up the canyon. I don't see a need to fool with that on a plan. I'll just experiment a bit when I am building.
Before supper, I did try the step up with a yard stick and 36" works fine. I think in the long run, I'll like to keep the middle open for a swing out control panel, swinging the detachable section from the wall, and for just turning around. Who knows, maybe I'll find myself in a wheelchair operating this layout someday.