One of the main uses for CNC machines like the Mill One is
You can of course, also check out Ayesha’s tutorial on PCB milling (https://sienci.com/2018/08/23/pcb-milling-tutorial/), which goes through a similar process.
Looks like according to comments online that the next frontier to getting good milled circuit boards is to use a mesh leveling system. This would of course map out all of the points on the PCB and automatically raise and lower the Z axis to compensate for any irregularities in the thickness of the board.
Chuck, from CHEP3D, also covers PCB milling on the Mill One, with his own way of using Easel.