I don't know a lot about most of them, but as for the quotes of St. Irenaeus, that is from a passage in which he is describing the beliefs/practices of the gnostic group started by Carpocrates. It is probable IMO that what he was against was not iconography (Christian images were common by the late 2nd century, e.g. in the catacombs), but rather against both the how and the who involved. That is, the Carpocratians believed that Jesus was enlightened, but that anyone could achieve the same thing, or even surpass Jesus. Thus when they made a likeness of Christ and put it right next to images of "Pythagoras, and Plato, and Aristotle," it was not in the same spirit that the Orthodox do it (with the difference between Jesus and the saints clear).