You're also conveniently forgetting (or, perhaps were unaware) that "young disciples" in that time and place were very likely illiterate, as were most people -- but especially those who were common laborers, such as fishermen and even tax collectors. The fact that MOST things, whether it be sales invoices, or histories, were not permanently written (written things were usually written on wet clay tablets that could be scraped clean for reuse), is further evidence of both later authorship (and Gentile origin). Jesus' teachings at that time were too unimportant to have been written -- especially in a permanent fashion. It was to difficult, too sparse, and waaay too expensive. No, I'm afraid the reality cards are stacked against you for "young disciples" authorship.
Your points are valid, mostly, although they didn't address the substance of my point. My point was how very young disciples of Jesus (only Peter and Jesus were required to pay the tax of a half-coin, so one coin in a fish was used to tax them, Peter and Jesus being the adults of the group) indicates that it could be 50, 70, even 90 AD, and the former young disciples of Jesus, who preached lifelong, decided later to pen their experiences, as older adults, put differently, preach and convert and disciple for decades, and later, consider their legacy for future generations, having come to accept that scriptures could be written beyond the established Hebrew Tanakh.
I'm a little older, and in the day of my (first) college experience, the Jesus Seminar, the most liberal possible group of Bible critics, affirmed that the NT was completed by circa 90 AD.
I currently attend English conferences, where I get to chair panels, choose abstracts for presentation, and opine on all kinds of things regarding dead authors' works, that are honestly somewhere between educated guesses and some kind of well-meaning apophenia or pareidolia, put differently, I get to constantly see myself and others spin tales and just-so stories regarding authors' works. Honestly, I try very, very hard to find substantive subtexts and critiques that relate to the language used in the words, I do, but I "get" how modern Bible scholarship is the same--take potshots at the text and make guesses, some educated, some not very substantive.
Fortunately, the Greek language used, and the countless insightful historical details in the NT, unavailable to late writers, since archaeology came to be only in the past two centuries or so, helps us date the Greek NT early. I also have considered that we have 27 NT documents plus apocryphal documents and even Talmud (which criticizes Christianity but also informs us that Jesus was crucified on Passover at 33 1/2, did miracles, and Joseph wasn't His father), !, and no counter documents saying "I was alive in 30-33 AD, Jesus never did X and Y and Z and Saul the Rabbi never did X and Y and Z--on the contrary, ancient Roman and Jewish historians affirm the Nazarene sect was a growing presence, early on, that is, the preaching WAS important before the written word was, and no scholar I know denies that Jesus lived in Nazareth, was baptized by John in the Jordan, and was crucified, or that He had many disciples, early on, soon after His death.
Please be a little more open to what I'm suggesting, and please learn to take non-forensic "studies" (aka textual pontificating) with a pinch of salt!