Accuracy option - I suspect the cutter/plotter users would choose this option,
and if so, somehow depict a CNC machine? I have no idea what a 3d printer looks
like.


CNC and 3D printers caught my eye. I’d suggest a laser cutter plus ruler. 

I suspect there’s more people using Inkscape to drive laser cutters than any other digital fab tool. It’s reasonable to go straight from Inkscape design -> laser cut goodness. CNC and 3D printing typically have extra/intermediate steps that will probably cause most people to drop into some other software before fabrication. (Eg extruding to 3D, or creating cutting paths that are the radius of the cutting tool away from the outline.) 

Cheers,

Julian