You are thinking like a Ivy League policy wonk. As if the president can actually do anything to grow the economy. What the president needs to do is not to implement some central government planning, but just to get out of the way.
If Obama had done nothing but golf and veto every piece of legislation that came up to his desk, the economy would be booming right now.
I would love to see a candidate state categorically that their plan for the economy is just to leave it alone.
A president can push congress to cut taxes, repeal stupid legislation like ObamaCare, Dodd/Frank, SOX and other job killing regulation. There’s a LOT the government can do to get this economy moving.