I won't say I've read all the Church Fathers, but recently I've studied parts of Adversus Praxeam by Tertullian, Dialogue with Trypho by Justin Martyr, and various bits and pieces of the others.
What you will find if you start investigating that tract, is that the church fathers are, for the most part, misrepresented and even deliberately misquoted. (Apparently there are entire books out there refuting that tract.) For example, they say that Justin believed Jesus was a created angel, citing one or two words from a ream of discourse in which he demonstrates that Theophanies, or passages in the OT where the "Angel of the LORD" interacts with the patriarchs, are actually appearances of the LORD Himself. In another quote, they make it appear Tertullian believed Jesus was not God... quoting a work in which he argued FOR the Trinity doctrine proper against Sabellian heresy.
Many of the early Christians, especially the Apologists, had flaws in their theology as they tried to apply ontological ideas to understand what, in Scripture, is described in strictly spiritual terms and not explained philosophically. However, with the exception of maybe the Shepherd of Hermas, all those guys you quoted believed in the Trinity. Origen was a little off track in that he screwed up trying to explain HOW the Son was "begotten," thus leaving the door open for Arianism to say that if Jesus was begotten at a certain point in time, then "There was a time when the Son was not" (Watchtower theology). Athanasius pointed out to Arius's followers that the Bible doesn't reveal to us when or how God begets a Son, so we ought not to turn to philosophy for explanations of this mystery as Origen did.
The brochure doesn't quote Ignatius for obvious reasons, although a later Watchtower article tries to misrepresent him in a fascinating way... by quoting exclusively epistles NOT written by Ignatius himself, and claiming that they represent his views. Here's the article that details what they do to mangle history: http://www.iclnet.org/pub/resources/text/apl/jw/ignatius.txt Of course, they rely on ignorance--the average reader is not going to dig up the genuine Ignatian epistles and count the references to "Jesus Christ, our God," or quotes such as these below:
"Await Him that is above every season, the Eternal, the Invisible, who became visible for our sake, the Impalpable, the Impassible, who suffered for our sake, who endured in all ways for our sake (Polycarp 3)."
"There is only one physician, of flesh and of spirit, generate and ingenerate, God in man, true Life in death, Son of Mary and Son of God, first passible and then impassible, Jesus Christ our Lord (Ephesians 7).
I was completely floored when I started to do research on this topic. There's a distinct feeling of violation when you realize you've been deliberately lied to.
I'm actually addressing a lot of the Biblical topics in that tract in my blog, "Sealed for Eternity."
Hope that helps for starters.
Because of Him,