Card game eh? ;D
I think 3D printing open source projects are going to be all the rage within 5 years. I have an idea for one as well. I have an idea for an on chain video game but I also want to adapt it to a physical game where all the pieces could be created by a 3D printer.
It really all comes down to proof of brain. If a project can create value and distribute that value back to the community it will go viral for sure.