What are the limitations of our current economy today?

We can observe everywhere around that offer and demand are facing one another but many transactions don't occur for the only reason that there is no money. The resource is not lacking, only the transactional tool --money-- is lacking. Most communities are undermonetized.

We are so accustomed to this scarcity of money that we believe it is a scarcity of resources. Wouldn't we be amazed if an architect said "I have run out of inches, I can no longer work", or a musician "My stock of notes is empty, I have to stop"? This is exactly what is done with money which is only a measurement tool for transactions (among other properties).

What is missing in the current monetary system?

Most problems come from the way national currencies are designed. They are centralized, scarce, proprietary because 85% of it is issued by private banks through credit. The rules of issuance are not democratically controlled, the monetary mass is not regulated by feedback loop mechanisms based on human resources, natural resources, sustainability issues.

Today's monetary system is still made to value what is materially measurable and what is scarce. Education, healthcare, mutual support, abundant but precious resources are not included in the monetary system if they are not made artificially scarce, and/or made measurable on a scale of materialistic value. Do water or knowledge need to be scarce to be distributed and regulated on monetized markets? Do health or education need to be valued on a scale of physical assets such as gold or a money made for transactions of material goods?

Evolution

It is likely that new free currencies are going to emerge in the next year. See Open money for instance.