That's an interesting twist. Scripture now contains everything necessary for doctrine as well as salvation? How do you support that statement? What about the Trinity? The hypostatic union?
Many of those we call church fathers were under the influence of the great explosion of heresy in various regions, Egypt being notorious for it. So their failure to maintain a strict and uniform doctrine indicated their fallibilities, not that of scripture.
Where does Christ say in Scripture that he is equally God and man? If you're saying they "failed to maintain a strict and uniform doctrine", and if Scripture "contains all that is necessary for doctrine", where is that doctrine spelled out in Scripture, and how could it be considered doctrine before it was defined?
What is ludicrous is that the Apocrypha, upon which these notions of Mary's sinlessness and ascension, were rejected from the canon of scripture (Council of Hippo) and were only included in the thirteenth century (Council of Trent).
You're referring not to the "Apocrypha", but "Apocryphal" books. In either case, you're wrong. "Apocryphal" books may not have been canonical, but that doesn't mean they contained a totality of error. e.g., if I taught a history class and remarked that the movie "JFK" was fiction, does that mean Kennedy wasn't shot in Dallas? Since the apocryphal Gospels assert the Jesus rose from the dead, does that mean he didn't?