I'm a fan of the information-economizing value of heuristics, though I certainly recognize that they can get us in big trouble. At a Jack Miller Center event a few years ago, Mike Munger said that whenever we say "the state should..." we should replace "the state" with "the politicians we see who actually get elected." That changes the game somewhat as when we're thinking about public policy, we aren't thinking about policies enacted by disinterested, wise, virtuous, technocrat-advised-autocrats. Rather, we're thinking about policies enacted by real people with real flaws and real limitations who are responding in real time to real incentives. Hence, the outcomes we see are a far cry from what a well-intentioned economist can dream up in his office.
Hence, I propose a heuristic: If it requires policymakers of above-average intelligence and virtue who are willing to act contrary to their incentives in order to work, then it is a bad policy.
It seems pretty obvious, and I'm sure it isn't original. And yet: how often do you hear people saying that we need to vote the bums out and replace them with the wise, the virtuous, and the incorruptible? How often are people shocked (SHOCKED!) that politicians respond to incentives? How often do people treat systemic institutional failures as if they are individual moral failings by people who are of virtue insufficient for their office? How often do we blame bad outcomes on "bad people" rather than "bad institutions"?