As one who also spent years in HO, I realized that because space is defined as BOTH length and width a similar "O" layout needs 4X the space to have the same operating characteristics and realism as does HO in the same layout space. That is because "space" is defined as length X width.
I think that a veteran HO modeler might be unhappy IF he attempts to have the operating possibilities in "O" as he had in the smaller scale. I think that we have two basic choices:
- A "model railroad"- with a good rendition of reality, scale modeling (sort of), with reasonable trackage, but fewer scenes. or;
- A "toy train". Look at a well-done toy train layout, and what matters is that there are lots of tracks to run lots of trains, and many accessories. This IS very much fun for those of us who loved this as kids and wanted all those sawmills, oil derricks, and other stuff we/ our parents could not afford. A toy train layout IS fun for most of those and also for most who will see our layouts as visitors.
No negative implied, and there are fans of each on this Forum and in the hobby.
But if you (being an HO modeler) want a similar"scale" looking layout, you have to compromise on the number of yards, have more off-layout storage like wall racks, fewer spurs and double track mains etc., and focus more on the scenery, buildings, etc, of the layout.
You need to be better with "fooling the eye"- using things like forced perspective, use of building flats vs. buildings, etc. and to compromise on the yards, and trackage.