Two rapid thoughts:

- Karma can not only be tied to a person. It can be emitted by a community, a company, a state, or any entity. The state also creates fiat currencies in the same way. The state prints money through the central bank, which generates state debt, and then reduces it through taxes. The same model can be applied to karma money created by a community.

- The idea of "utility-based credit" is interesting, but I believe that the tax and support system is the easiest way to implement this. Harmful activities must be punished with taxes, while beneficial activities must be supported. It is very difficult to implement this into a monetary system at the algorithmic level. For example, who decides what is beneficial and what is harmful?