What if items from the WANT category are moved to the NEED category when either 1 of 2 things are met. It's empirically shown to improve the health of the owners. Or it's possible to create the item for everyone on earth, meaning we have the resources/manufacturing without harming the biosphere.

With these 2 rules we should see a steady increase in QoL for everyone.

The main problem with the whole idea is that it is inevitable that an exchange rate will be set and they will be traded. What does a NEED collector do with the collected NEED currency?