Really enjoyed the video today on New Year's Eve! What a totally massive structure. Don't know about turning it into modules/layout, but if that happened, it would certainly be impressive.
Since I'm modeling prototype railroad features on my modular layout, I can get the width pretty close to prototype, but never length. Nearly all of my LDE's are anywhere from 1/2 to 1/4 the actual prototype length, which means any operational LDE (as opposed to scenic LDE) is at least 12' long, with most of them being 24' long and one (for sure) that will be at least 36' long (in an "L" shape).
Same goes for my freights. A Big Boy would regularly pull trains of over 4,000 tons, which translates into trains of around 100 cars depending on empties vs loads. My passing sidings are regulated to a length of 9', 7 1/2", which only accommodates a Big Boy + 30 forty foot cars + a caboose. One third length essentially.
Anyway, thanks for the video!