I think this is a great concept, but I think the main issue will be dust control from the CNC portion. It might be best to include some form of blower pipes or extraction pipes into the design. I have a Carvewright machine and it produces a lot of dust and needs constant cleaning of it's sensors. Keeping the mechanism clean will be crucial to do laser and 3D work after milling any material. But for hobbyists it might be a great 3in1 machine.