Iran's political system is one of the greatest and an exemplary to all the other under developed nations especially the Islamic states. ...
If you think a peaceful and orderly transition of Prez is the key to a greatest political system, then you are right.
However political systems is just a government system in its core. And good government system must provide -------------------- you guess it!!! Good governance.
Chinese do not have a political system (your words) so to speak, and yet they have much better "governance" compared to the largest democracies in the world aka India.
Thus if you consider the important aspect of "governance" in the Iranian case, you will find that it had failed miserably in the last 30 years. News of an Oil producer, and not knowing how to build/maintain refineries is just a clear example of MIS-GOVERNANCE.