Mark:
I'm hoping this time I will not get "analysis paralysis".
For examples, owing to my findings with the "hands on" experience, I have definitely eliminated a big source of distraction: TOC19 steam in HO. That has been a distraction for decades. Way too finicky. It would most certainly be a source of constant frustration when trying to run/operate the trains.
AND, it looks like the 3-rail allure may be sorting itself out, too.
What would remain is to decide to return to my love of Ozark railroading, or return to my childhood roots and reflect Kansas City. I'm confident I could enjoy either. That will help to be decided with pencil and templates (track planning), as well as weighing my pros and cons of the two themes.
NICKAIX
You have just outlined what my concerns were, and are about trying again with 3-rail. It is very likely that I've played with scale trains too long to move to 3-rail at this point in my life.
Shame we can't do it all... ain't it? 
Off to ship a couple packages of standard S scale rail bundles I've sold to a couple of acquaintances!
Andre
