Evolution of the Senior Pastor

A few weeks ago I talked about the joys of my new life as a retired person. In this new life I spend around 50 hours per week either in class, studying, or reading in preparation for those classes. Because something is not right with me, I have added a significant amount of additional reading and study on a few topics that interest me outside of my coursework.
One of my major projects this year is to evaluate the Church in America and to take an academic approach at recognizing some major issues in hopes of coming to useful conclusions. So far it has been interesting to trace the earliest Pagan and Christian literature we have outside of the Bible to notice some trends emerging. In its infancy, the Church demonstrates an uncompromising commitment to Christ and works to live at peace with the Roman Empire and in recognition of their Jewish roots.
By the 4th century, we see various Bishops such as Ambrose of Milan wielding their influence and political power. These Bishops actually experienced open relationships with the emperors (Constantine in particular) and were even able to begin outlawing all religions other than Christianity. The church leaders gained an increasingly greater level of power while the “average” Christians seemed to gain less influence in their own churches. To demonstrate this change in thinking Ambrose says, “Palaces belong to the Emperor, and churches belong to the Bishop”.
It is interesting to note that as time moved on, the numbers of “Christians” dramatically increased and therefore the political influence of Christians also increased. Along with this, church leaders began to say things like “We are the head of the church”. Could it be that this mentality is the distant ancestor of the system we possess today with “Senior Pastors”? I am not sugessting that churches should eliminate the title of "senior pastor" because the culture in countries like the USA virtually make it impossible for people to understand the structure of a church without this position. But I do wonder if some of the problems in many churches today come from people believing that they are “the head of the church” while somehow forgetting that Christ is the head.
How many times do you hear senior pastors and congregants speak in terms of “My church or your church”? Does this type of thinking make church leaders too powerful and therefore too susceptible to needing to have it “their way”? Sadly, as the early Christian church shifted from a persecuted body of people all pursuing Christ and desiring to know and please Him to an organized political force led by powerful men, we see less and less evidence that these people had any relationship with God. History proves that some of these men actually did not have a relationship with God but enjoyed the power given by leading churches.
So as I leave Israel next year and most likely re-enter the Church world as a “Senior Pastor”, or even better, simply as a “Pastor/Overseer”, what can be done to avoid the mistakes we see so often today? Can churches today find persons for leadership like the ones described by Origen in the late 2nd century when he said, “We call upon all of those who are competent to take office, who are sound in doctrine and life, to rule over the churches. We do not accept those who love power”. How can Christian leaders ensure that they do not “love power” and how can churches ensure that their leaders do not “love power”?