Mark, I was reviewing the last SCARM file I have for your layout. I think you have enough room to add 4 to 6 inches of upper town. At 6 inches the total reach would be 36 inches to the window. A little long but the add could be a drop in so you could easily move it out of the way if necessary. (Kind of like a pop up section.) I do think the you should have wider sidewalks and more curve clearance. Just put in a rectangular section inside the curve.
As I recall the plan was to have 042 minimum curve on top. Not sure what the top flex track curve came out to be. Guessing 3 inches would be plenty for what you are running. Jeff
Is the watch tower new? I thought you had a picnic scene there awaiting a few pine trees. ?