If a universal basic income started today with the stipulation that you had to put 40 hrs/wk towards making the world a better place or solving societal problems, how would you spend your time?

I'm with you, from the urban design perspective. Our cities should be fitting into nature as best they can, not steamrolling thousands of acres of ecosystems. You'd also free up the labor of all the people who will have to fix this mismanagement down the road.