For those who are satisfied with a small layout, there is no question is has cost, space and time advantages.
As for me, swtiching/shunting cars, or running short trains sbort distances, while a fun aspect of the hobby, it does not fulfill my interests.
Another aspect is scenery. Hard as I tried on a previous layout, I simply was not happy with a narrow shelf layout that only models what is along the right of way.
I think many times the big layout trap, is trying to do too much simply because you have the space. My new layout will fill a 1500 sq ft basement, but with wide spacious aisles the benchwork is only about 950 sq ft.
Rather than cramming in more features, curves are bigger, yards are longer, scenes are deeper and include more “non railroad” features.
My passion, realistically long trains traveling thru scenes with depth and context.
BUT, I will have switching and other more “intimate” operations as well. Largely removed from the double track mainline, there will be what amounts to an “Industrial Switching Layout” that can be operated completely independent of the mainline.
There is no universal ideal layout, only what is right for you.
I have never “started over”, sold off a bunch of stuff, changed guage or era once I figured out at an early age, what I liked and wanted to model. I have vertually nothing that is outside the era or theme of the currently under construction layout.
What a great hobby. Something for everyone.
Sheldon