I think they should do just 1 classic Stern just to see what happens. Test the waters a bit. There's MM, but what if you take a step back for a simpler pin. No elaborate side graphics, ramps, and not too many proprietary parts. If CPR can make playfields, backglasses & plastics, what's not to make the rest of the machine around it? It doesn't even have to be 100% like the original under the PF to do it.

The only choke point I could see would be score displays. Just about anything else would be "off the shelf" hardware. If a Big Game(for example) was using modern Stern flippers, no biggie. Set it at a good price point, and it just might be something good here. As games get older, more pfs get blown out, things get destroyed/parted out.

Ball save and switchable bonus lanes come to mind.

With new rulesets, just like on BoP, it would be a given to switch between the rulesets to taste.

I do the same thing(doodle playfields) when I can't use the computer at work. Scan 'em in so we can see them.

I think I've thrown out hardware with better display capabilities than that.