Markan Priority vs Matthean Priority

I'm quite enthusiastic to be having a discussion with another major in Biblical studies. I wish you the best in the future to come with your work and research. I'll agree with your first premise that most NT Biblical scholars agree that Mark's Gospel was written first. However, I believe our knowledge of scripture can be flawed. Just like my opponent, I'll also be offering two basic contentions. First, the early Christian writings on the topic say that Matthew was written first, and secondly, Textual evidence. Early Christian Writings/Farmer's Argument"Augustine was not the first to articulate this view [Matthean priority], as Irenaeus and Origen, among others, shared this ordering. However, Augustine was the first author to give a detailed scholarly textual analysis of the three texts' interdependence, and to articulate a theory for the express purpose of explaining this fact. ... [1]The Church Fathers who wrote about the order and authorship of the canonical gospels all supported some basic ideas of the Augustinian hypothesis. The fathers whose writings survive and who wrote about authorship are almost unanimous in agreement that Matthew the apostle was the author, wrote first, and did so for the Hebrews in their language. A number of sources in antiquity asserted that Mark wrote his Gospel after Matthew based on the preaching of Peter. Various elements of this tradition are found in the writings of Irenaeus, Origen, Eusebius, et al....Jerome [c.150 AD] even claimed to have seen the original Aramaic Matthew in the library of Pamphilus the Martyr. "As the church rose out of the mission to the gentiles, it is interesting that the church fathers supported the Judaic gospel of Matthew instead of Mark. Also consider that they testify that Mark was the companion of the Apostle Peter in Rome which became one of the five sees of the early church (Rome, Constantinople, Antioch, Jerusalem, and Alexandria, Egypt). Unless the tradition of Matthean priority were very early, it is unlikely that they would all arrive at it independently." [2]"There are NO scraps of Mark know in existence that predate about AD 350. There is a scrap of Matthew from AD 160, and a scrap of John from AD 120. As a side note, the copy of The Didache is dated to be AD 100!" [3]Farmer's Argument"IX. It is possible to understand the redactional process through which Mark went, on the hypothesis that he composed his Gospel based primarily on Matthew and Luke. B. FAVORITE EXPRESSIONS OF MATTHEW AND LUKE In Rev. Sir John C. Hawkins's Contributions to the Study of the Synoptic Problem, he lists 19 "favorite expressions" of Matthew that are not unique to Matthew—14 of these are found at least once in Mark, and 10 also in Luke. Likewise, of 7 Lukan expressions, 5 are paralleled verbatim in Mark and 2 also in Matthew. There seem to be no such expressions characteristic of Mark, however, which show up in either Matthew or Luke. There is only one solution that affords a ready explanation; namely, that Mark copied Matthew and Luke. XVI. A historico-critical analysis of the Synoptic traditionThat form of a particular tradition found in the gospels which reflects an extra-Palestinian or non-Jewish provenance is to be adjudged secondary to a form of the same tradition which reflects a Palestinian or Jewish provenance....in questions of literary dependence between two documents, that document is to be adjudged dependent which contains features of a secondary character. The following are to be regarded as evidences of a secondary character: Manifest misunderstanding of what stands in one document on the part of the writer of the other; C. Considerations which sometimes have influenced students of the gospels in their statements about the Synoptic Problem, but which are either irrelevant or inconclusive. The Christology of a given passage. Since the letters of Paul disclose the fact that Christology was already both complex and highly developed in some circles in the period before the gospels were written, and since our knowledge of Christological developments in the Churches in the post-Pauline period depends upon a correct solution to the problem of the chronological and literary relationship between the gospels, and not vice-versa, the Christology of a given passage in the gospels affords the critic no reliable criteria by which to adjudge it primary or secondary to its parallel in another gospel." [4]Textual Evidence1. "There are a significant number of places in Matthew where the parallel account in Mark makes more sense to have been edited down than for Matthew to expand. It is possible to read Mark with the hypothesis that it came from Matthew and run into no redactional problems that challenge said hypothesis. However, reading Matthew as a redaction of Mark does cause such problems. 2. There are places where Mark uses a certain word but Matthew does not, even though he used that word in other places (for example "pherein"). This makes more sense with Mark editing Matthew than of Matthew copying Mark.3. There are places where Matthew has phrases he likes and uses them consistently. Mark has parallels of most of these accounts and is very free in his translations of the phrases. It makes more sense for Mark to be free styling from Matthew than it does for Matthew to be forcing the phrase into his wording whenever he sees it in Mark. One of these phrases is opias de genomenes, found first in Mt 8:16 and Mk 1:32. Markan priority has to conclude that Matthew copied the form exactly as Mark had it the first time, then always and consistently used the same grammar whenever he found a similar phrase in Mark and introducing it himself in Mt 20:8 which has no parallel in Mark.There are places where Mark combines details from both Matthew and Luke. An example of these duplicate expressions can be seen in Mark 1:32 compared to Mt 8:16 and Luk 4:40:- Mk 1:32 When evening came, after the sun had set, they began bringing to Him all who were ill and those who were demon-possessed.- Mt 8:16 When evening came, they brought to Him many who were demon-possessed; and He cast out the spirits with a word, and healed all who were ill.- Lk 4:40 While the sun was setting, all those who had any who were sick with various diseases brought them to Him; and laying His hands on each one of them, He was healing them.In these parallels, Mark combines the introductory phrases from both Matthew and Luke. In this case, Markan priority would require that Luke know of both Matthew and Mark and consciously choose to use the exact phrase that Matthew does not. However, if Matthew writes first and Luke second, there is no such problem.4. Matthew leaves semitisms in place where Mark smoothens them. This includes wording and patterns that Mark breaks. Yes, Mark has eight semitic words, but Matthew has many more semitisms (so does Luke, a plethora of semitisms). Many of Mark's semitisms seem to be added for drama while Matthew's flow naturally.5. Adding to the semitisms are 12 times where Matthew (and Luke) uses the participle of a verb while Mark uses the past tense. Using a participle for the second verb in a set (and he answered, saying) is well-known when coming from a semitic language (all over the Septuagint) but is not used in normal Greek. Mark also uses these participles but not as often. It would be more likely to edit them out than to edit them back in. Many more examples exist where Matthew and Luke agree with one another in wording and Mark is different." [5]