I use linux for all my comouters and I have for 10+ years. So just don’t ask me about windows 
Yeah, the zero is fun, but at $35 a bigger pi is just worth it. It can run one printer without a camera fine, but I do see a speed boost with the 3B even with a minimal setup. I haven’t done extensive testing on the cnc.js plugins either and I wouldn’t be surprised if some of them were also resource hogs. I also appreciate the ethernet and multiple USB ports on the big pi.