Comment by jsheard
Interesting idea, but the generic green PCB is a bit of a missed opportunity. Some manufacturers now offer transparent solder masks which emphasize the copper traces and can look really cool with a clean PCB layout.
e.g. https://hackaday.io/project/194683-plasma-toroid-sky-guided-...
It's also becoming possible to have transparent rigid PCBs as of quite recently: https://www.pcbway.com/blog/News/Transparent_Rigid_PCBs_Laun...
Naturally it does mean you can't have a ground pour, so the PCB needs to be designed to look nice with it.