Your points are very valid, and I appeciate your candor.
As I pointed out elsewhere on this thread, Protestants really don't hesitate, in general, to use material that is extra-biblical.
Bible dictionaries, commentaries, etc... in use within Protestantism have lots of explanatory and background material that is based on secular scholarship, archeology, Jewish tradition, the deductive reasoning of other Protestant theologians, etc... Protestant pastors have been using such sources for a very long time to spice up their sermons.
The point I made earlier and that I reiterate is that the one class of extra-biblical background and explanatory writings that are essentially never used within classical Protestantism (at least as I have experienced it) are writings done by Christians themselves from the early centuries. These are rigorously excluded from consideration except in very limited situations.
I think that is a very valid point. Protestants rarely go back to the writings of the early church father. I never did, only because I thought most Christians were in agreement on many of the issues that we discuss here. Protestants are ignorant of history and it shows.
It was only after reading some of these disagreements that I thought one has to go back to the early church fathers and look at the history of the Church. Trouble is, as we see here, there are different ways to interpret history and the church fathers (like Augustine).
One thing I do appreciate about the Orthodox and the (cough) Catholics is the references to the fathers. I wish more of my Protestant brothers would do the same. As some may know, given a reference and the opportunity, I will go out and read the work. However, while the early fathers might have been godly men, I don't revere them and often read them with a critical eye-exactly the same way I read Calvin, Wesley and Spurgeon. I'm basically a cynic.