Attempt a blank-slate reboot of macroeconomics. Using data, build a framework for evaluating macroeconomic models. Develop and test models without prejudice.
Human civilization operates at a higher power density than the core of the sun. We should understand it. But economics is stuck a natural philosophy, and most of it is actually anti-knowledge.
Success here will unfortunately require significant effort (10-15%) be spent on evangelism, including criticism of existing economics.
The main consumer of economics is government and there are strong incentives to exaggerate the effectiveness (either positive or negative) of economic theories and policies based on them.
You will have to work very hard to avoid politicization.
Recent work in thermodynamics (Tim Garrett, Jeremy England) may be helpful on the theory side; machine learning on the empirical side. To get financial data, homomorphic encryption: https://numer.ai