Apparently the best way to learn what designs DO NOT work reliably is just to make every 3D printing mistake in the book as we go. Which we are doing quite well.  For example, the image below shows the result of printing the enclosure design with a different filament type (PLA in this case) to see how it would work.  The result indicates insufficient print-bed adhesion as well as (possibly) over-aggressive cooling tuning resulting in pull-away and part warping.  New design will have a more filled-in base layer.

Things always look wonderful in the CAD software, but then you hit print and ... <doh> ...