Hi Scott,
Visually, the blue line loop is going to hide a lot of the yellow underneath. Does Railmodeller have 3D objects so that you can see that? Hidden switches will be the ones with derailments from finicky cars.
Ideally, having the loop on a mountain and the yellow line running outside the mountain (steep, cliff sides) would solve that, but, it looks like there isn't space for some O90 on the bottom yellow.
I know the space is limiting the design. You will find the yellow line on the angle and the passing siding will be a pain because Murphy's Law will require that you will have to access the track along the wall many more times than you envision. If you set the base table height at 40", you could make a roller seat to scoot under that area. I would fill the openings and put two access hatches in to reclaim the real estate.
I do like how the design operationally forces a long run to change directions to access the sidings. More play value.
You are close to a good design.
Are the gray items the mechanicals for the house?
The Ross track is very nice looking track and the switches and motors are solid.
here is a build thread where you can get ideas. Look for the access hatch technique and the scooter seat for sitting and working under the layout.
Hidden Pass Junction by Alex Muller(Ingenerio No 1 - OGR forum name)
