One thing you can look at is what Paul is focusing on throughout these verses. He talks more about the Power the person has, not the person themselves. Even if the ruler is evil, God gave him or allowed him to have the power that he has. You should obey them even if they are evil. Just look at how Jesus acted when he was acused by Pilot. He knew that he did nothing wrong (How could he? He is God!!), yet he obeyed the power that Pilot had over him in the governmental aspect.
Remember:John 5:5-12 Blessed are the MEEK: for they shall inherit the earth. Blessed are they which do hunger and thirst after righteousness: for they shall be filled.
Blessed are the MERCIFUL: for they shall obtain mercy. Blessed are the pure in heart: for they shall see God. Blessed are the PEACMAKERS: for they shall be called the children of God.
Blessed are they which are persecuted for righteousness' sake: for theirs is the kingdom of heaven. Blessed are ye, when men shall revile you, and persecute you, and shall say all manner of evil against you falsely, for my sake.Rejoice, and be exceeding glad: for great is your reward in heaven: for so persecuted they the prophets which were before you.
We are supposed to be meek peacmakers, what ever persecution we withstand now is going to be a reward in heven.