What makes a performing leader?

Identifying what really matters for growth is, most of the time, like spinning around a vicious circle. All that causes growth is also its consequences...And then you have exceptions: autocracies grow (Singapore), bad institutions don't matter (China), trade openness neither ( was it ever found significant?), resources are a blessing but also a curse...so I guess there is no secret to growth.
But come on there's got to be something...what could be the common thing that all countries that do well have in common? Answer: great leaders. Get my point? Zimbabwe's official exchange rate or trade policy doesn't matter really in as long as Mugabe is in charge...
Econometrically, this ain't easy to show...some tried and found that leaders do matter.

Now comes the interesting question. If good leaders are really all that matter, we can now ask ourselves what makes a performing leader? Is it his looks? His profession? His religiosity? His IQ? Ryan Enos at UCLA asked himself if IQ really matter for US presidents. Here's his graph:
So here's what I'm trying to find out (with econometrics or not): What characteristics of leaders determine country economic performance and second what do performing leaders have in common? IQ might well be one of these. Good idea???