I think QR codes are also fine considering we are moving more towards the digitalized zone and everyone carrying their phone-based QR scanners. It's crazy.

I think OP should take this idea further with the minting of some historical papers too. You know those papers that held importance in human history. Gradually a digital library can be created using this method and thus preserved over blockchain forever. I am not sure if minting it publicly will reduce the value of its ownership and also the auction value but it would be good for forever storage.

The papers like the first signing of independence of America (or any country) with images, or some important document which expose the Nazi deeds and what not. I am not sure if this would be relevant or not but could be another good project OP can think about.