Even those Fathers whose writings have been readily translated, usually compromises just a sample of their overall work.
For example the Alexandrian Patriarchate was the most prestigious and most theologicaly advanced in the entire empire from the 3rd century to the 6th. Yet we assume all there are is the writing of Clement of Alexandria, Origen, St Athanasius, and St Cyril, perhaps if you are familiar with non-chalcedonian authors you would include Dioscoros. To say this assumption is misleading would be an unnderstatement. There are Patristic writings from this era, some in Coptic monasteries, possibly fragments in Sinai and just alot that has never been translated out of greek and coptic. I believe its quite recent that the most ancient prayer found to the Theotokos dating back to 240 a.d. was revelaed to the english speaking world and was an Alexandrian fragment.