something to consider in your planning:
I did a quick look at the IHB operations maps. which I found here: https://www.dhke.com/ihbarchive/ihbhst.html. they had significant miles of single and double track mainline. if you have interest in an interchange with a larger railroad. you could reduce a section of benchwork in width to represent distance from one scene to another. for example: if the benchwork along the left side wall in the drawing was reduced to say 14"-16" in width. it could represent a separation from a larger switching area at top (of your drawing). and another switch area with an interchange at the bottom.
that's one idea. if you're interested a representation of the actual line, delve into the maps and figure out which sections of the railroad may fit your space.
