This post makes me think pinball should go open source...
A few guys that are way more into it than others design the layout collaboratively. Have some artist friends design the theme. Programmer friends to do rules lights sounds and dots.
Be able to buy kits for playfields, wiring, controllers (raspberry pi, beaglebone, etc) and DIY.
Alternatively, everything will be online for free. So if you have access to a 3D printer or a CNC you can DIY very easily.
Spitballing, of course. But I wonder how this isn't already a thing.