Looks awesome in acrylic. Do you think you could design something like this using OpenJSCAD? Go here: https://www.youmagine.com/designs/smartcore , then scroll down to V1.2, click the gear, and select ‘Edit in OpenJSCAD’. You type in wood thickness, rod thickness, desired bed size in X and Y then on the left side change it from All Printer Assembly to just ‘walls and rod sizes’. It tells you the exact dimensions to cut all the wood, and the size of rods to get. Then it lets you download customized STLs for the exact thickness of wood you have.
I would love that for your design and maybe even for a version 2 of the MPCNC. Imagine somebody just inputting the size of their conduit/tubes, diameter of router, and desired bed size and it comes back with custom STLs and tells them the exact size to cut all their conduit tubing and belts.