I'll look at making some 2" risers for the current pieces that will bring them up higher and possibly making some 6-6.5" tall wall segments. That should allow everything to case at least a 4" shadow. Will that help?

Beyond the HGL issues how does it play?

I need to make some more ladders, and then, with the height differences possibly some flat walkway pieces that can be used as either walkways between segments or sloped ramps for walkways between differing heights.