Yes, Jesus is God manifest in the flesh. God incarnate. Yet Jesus Christ, the Lord, did not write any parts of holy scripture. You could point to the ten commandments on the tablets of stone that are said to be written by the finger of God in the books of Moses. But since Jesus had not yet been revealed it would be a bit of a slight of hand to say that Jesus, the man who walked the Earth, wrote the ten commandments with his flesh finger.
Did God not speak and humans wrote as God directed?
Yes, God did inspire human beings (sometimes by direct speech to them) to write the holy scriptures but isn't that the very thing I have already said; specifically, that God did not write the holy scriptures, people did.
I am not arguing that God did not inspire the writing of the holy scriptures, on the contrary I affirm that he did, but rather I am affirming that people wrote the holy scriptures under inspiration from God. People did it. God inspired it. The Lord, Jesus Christ, did not write any of the new testament scriptures. He inspired them all and wrote none with his own earthly hand.
Jesus is far, far higher than Mary.
The Lord, Jesus Christ is God so he is more than "far far higher than Blessed Mary" He is infinitely higher and greater and more glorious and purer and is in every way greater and better than is the Blessed virgin Mary because Blessed Mary is a creature and not the creator.
The book of Hebrews outlines how Jesus is higher than all things. Please note that Mary is only mentioned in a few short passages and no more. She fulfilled her role in giving birth to God in human flesh. She cared and nutured as any flawed [caring and loving] mother can do. God was pleased with her actions and blessed her for it. That's the extent of her role. Mary was very likely illiterate
As far as I know you are illiterate in ancient Hebrew as am I yet God is pleased to be gentle and kind to us and to allow the faithful to participate in his work of saving the elect. Blessed Mary's role is more than the things you mention because her role is recorded in holy scripture for our instruction as, indeed, are all the things in scripture recorded for our instruction.
, which explains why she treasured things in her heart rather than on paper.
I imagine that Blessed Mary treasured many things in her heart and who is to say that she may not also have treasured things on paper. If she did then none of the paper she used is still with us today, perhaps some of the words she treasured are. There is evidence, albeit only indirect, that Blessed Mary was a principle source for saint Luke's holy gospel.