I would get rid of the center portion to give yourself the luxury of sitting in a comfortable chair to operate. Second, widen the bottom portion of the remaining
extensions to run 72 inch or 80 inch super elevated or canted curves. Sometimes less is more.
I run an around the wall layout just for that reason. One can still add a lot of detail .
This side is only 18 inches including the road.
This side is 22 inches with the road.