I settled on a design that I thought would prove the most robust after certain compromises were made: Stiffness had to be weighed against portability and speed with budget.
The end result is a machine that is by no means industrial, but is very versatile. For instance, the plate that mounts the router spindle can be swapped for a plasma cutting setup. I can cut most non-metallic materials and even some non-ferrous metals (at slow speed with a router spindle).
The cutting product on the video is unimpressive, a few scribbles I threw into microstation. I have, just recently, cut some geometric patterns with great results. So far, I been within +/-.01" accuracy.