>In my opinion, an economy is too important to leave to governments to run and tune.

But isn't that decision itself a governing decision, just one where we decide to tune for competition (for example)? It seems to me you can't avoid governance, as soon as there is power, there is either governance by the strong (robber barons) or by a system which tries to balance and - as you called it - tune things (e.g., an elected government enforcing anti-monopoly laws to improve competition)