If one is not concerned about access to the center (if there is access along both long sides of the layout, and if a 36" reach from edge to center is OK), then there is room for a small yard, and additional town, industry, or perhaps the two Menards tall buildings - they have a York Hotel and an International Headquarters "mini-skyscrapers" which would make a striking effect.
The yard has a short switching lead, so that the yard can be switched without fouling the "twice-around" mainline.