Well of course he didn't deify Mary. If he did he would have been a rank heretic and his Epistles would have been speedily burned rather than circulated to all the Churches. If he deified Mary we wouldn't be reading him at every Mass practically.
And yes, the problem is one of "who gets to determine which Scriptures have weight." I prefer to side with the majority on this. And that's the majority over 2000 of Christian history, with special emphasis on those writers of the early centuries known as the "Church Fathers".
Not only MIGHT we say that Mary's grace ALL comes from Christ, we MUST say it. Not a stitch of it is her own. From the definition
All know, likewise, how eager the bishops have been to profess openly and publicly, even in ecclesiastical assemblies, that Mary, the most holy Mother of God, by virtue of the foreseen merits of Christ, our Lord and Redeemer, was never subject to original sin, but was completely preserved from the original taint, and hence she was redeemed in a manner more sublime.Everything she has, she gained from God who saved her.
I do not see how Mary escapes the original sin given she was born into the family of Adam and Eve.
I personally like Moses writings and Jeremiah is one of my favorites, but not to the exclusion of the rest of them.
If she had never sinned, she didn't need God to save her. She could have saved herself.
If she needed God to save her, it was because she had sinned and couldn't save herself.