Having spoken with the awesome Jon Ericson, I can officially state that the proposal to put questions of macroeconomics in scope is the consensus among the Community Managers.
To wit:
I talked with the other CMs and we agree that the econ proposal won't actually overlap much with what you are trying. In particular, we hope it will be academically oriented in a way that Politics won't be. And I think expanding your scope (especially if it's a bit more technical in nature) would help out.
I have updated the On-Topic question thusly:
Just to clarify, Macroeconomics is specifically on-topic. Most public policy questions involve economic matters, so if you just need to understand how an economic principle works, ask away!
In short, let's try to keep these related to politics, but yes, ask away!