Andi I think one of you earliest posts may hold the key for you. I'm sure I remember you mentioned adapting local sites to add a railway.
That actually made me think about working up an idea I have had in mind for years and I took the photos of this local setting.
There is a small workshop about 300 yards/metres from my home. Although nowhere near a railway of any gauge it looks like it would be possible to adapt the site so that a single siding runs from the right hand side, then in a curve to keep it level over the street into the stone building on the left. The transit pick-up is sitting where the fictitious line would run. Plenty of scope for view blockers and interesting levels etc as the street is on a hill and it also curves.
Two more photos are on this under construction page on my website here - http://www.island-publishing.co.uk/developing_theme.htm
My suggestion is go back to your roots and do what fits your original vision based on those real settings that inspired you buildings.