You address an important topic, but I think the problem at hand comes from a more fundamental dysfunction within the system. Once a president is elected into office, he/she is in charge for a minimum of four years, almost guaranteed. We can't simply rely on improving the chances of getting better people into office for at least two reasons: a lot of damage can be done in four years, and even then, most of the electoral branch isn't elected by The People and at least some of it is allowed to carry influence from one president to the next.
I believe the most effective way to solve this problem will be to approach it from many angles with the ultimate purpose of restoring accountability to the executive branch. Improving voting methodology seems to be one of many possibly useful angles. Another might be to put weight on congress to begin scaling back the powers of the executive, such as by repealing the Patriot Act, defunding the NSA, etc. Another still might be to support legislation to protect the voices of other power structures and communication enablers, such as the internet, journalism in general, and organizations like Wikileaks.
Sorry, I suppose this doesn't really bring any new insights to the table. Rather, my point is that there's this really big problem (an overly powerful branch of government) that's been brewing for a while, and it's going to take a lot more than a single fix the repair the whole machine.
Of course, any single effort is better than no effort---I absolutely do not wish to discourage!