The CNC controller
After a lot of searching, and being totally new to CNC milling, I decided to go for a commercial solution and finally settled for this: Mk3/4 controller with enclosure and accessories
Although not cheap, this package offered about everything I would need (e.g. the software also included measuring the warp of a PCB and adjust the gcode program accordingly so that the cutting depth is equally deep everywhere). Convenient as well, is that they offer a decent enclosure, i.e. a complete package with all the needed software.
I’m sure I could find a cheaper solutions by going open source (e.g. Grbl, TinyG, etc.) and a lot of experimenting. But when you’re completely new in this field, it can be a bit overwhelming to figure out everything you need to know.
Assembling the USB CNC controller went quite smooth (the instructions were sufficient, even for a newbie like me).
I took the opportunity as well to upgrade the Chinese cabling with something more decent (including properly shielded cables) and connectors that can stand higher currents.