However, if one lets go of the ego of SOLA mi, and reads what early Christians actually thought, then you have...
...to also believe gnostics, heretics and others.
I think that it is cute that you will count Augustine when he allows for perpetual virginity, but will throw out everything else he says when it comes to soteriology and other doctrines Rome has rejected.
Many early Christians were also Premillennialists, and Augustine was once one, before he switched to what Rome now holds which is largely an Amillennial view. So if we look outside of Scripture, then which best represents the eschatology of Christ? Premil or Amil? (Sorry Preterists, you weren't well represented back then)
We stick with Sola Scriptura because God doesn't change, and neither does His revelation. The inspired texts locked in time serve that purpose well.
It's pretty typical for Catholics to cherry pick what they want to believe to support what they want to believe. They do it with Scripture and they do it with extra Scriptural writings.
There is no consistency to their decisions. It's all what their itching ears want to hear.
We stick with Sola Scriptura because God doesn't change, and neither does His revelation. The inspired texts locked in time serve that purpose well.
Truly, Catholics adjust Scripture to fit their beliefs. Protestants adjust their beliefs to fit Scripture.
"It was not the visible sun, but its invisible Creator who consecrated this day for us, when the Virgin Mother, fertile of womb and integral in her virginity, brought him forth, made visible for us, by whom, when he was invisible, she too was created. A Virgin conceiving, a Virgin bearing, a Virgin pregnant, a Virgin bringing forth, a Virgin perpetual. Why do you wonder at this, O man?"Where he relates what has been believed by all Early Christians since APostolic times to his writings on soteriology?