What part of "few and far between" do you not understand? The latest ministry of any of those you mentioned was Spurgeon, who died in 1892. That's pretty far from "common" wouldn't you agree?
If seminary is a “necessary” qualification, and if your point is that Scripture sets the precedent by the “earthly ministry of Christ,” then there should be no “few and far between.” I think that the passage refers to discipleship (which includes church edification), not necessarily formal education.
I agree that seminary is important, and pastors can benefit a great deal from such an education. I would prefer that a pastor have a Masters degree – perhaps a BA – related to Christian doctrine (I’m less concerned about a MDiv, but at least a degree that examined hermeneutics, scripture, and provided a good overview of theological issues in our times). I would like to know that he worked through his faith and defended his beliefs in an environment that is provided at seminary. But too often I believe we simply look at degrees and personality as the primary qualification.