Why do you think need creat bill, sound like physical bitcoin and centralization. Bitcoin has been created for decentralized financial economy without printing physical money. Now if you are wondering printing something like physical bill then it will hit decentralized system. Also it would prevent financial freedom, and of course we need third party for implement something like that. I don't like to see physical bill instead of p2p electronic system. Current bitcoin uses system is fine for me. We just need increse physical use of bitcoin like buy goods etc.