Yeah, 10-4.
I was thinking as I read what you wrote that I didn't start out thinking of Theotokos as a "title" but as a sort of "term of art". I really did come to it from the POV of Christology -- Second year, first semester, Church History, Trinitarian and Christological heresies and resolution. So I, at any rate, was not at risk for thinking that somehow Mary was older than God.
I asked a non-theologically trained person what the term "Mother of God" meant to them. Needless to say, they did not come up with "it was a term to combat Nestorianism" :)
Mother of Jesus will suffice. And, for Salvation's sake, Mother of my Lord is also biblical.
Mother of God is not a biblical term and has many implications.
1)One COULD think that this means that Mary was older than God (not the councils intent, I know, but that's what my non-theological friend thought it implied so it is a real issue)
2)Since God is Father, Son, and Holy Spirit, indivisible, Mary is the mother of the Father and the Holy Spirit (also not true, but it is a possible source of confusion)
By calling Mary the mother of Jesus, you firmly place Mary as Christ's biological mother and then can define Christology not upon whom Mary was, but who Christ is.
Jesus was incarnate God- eternally preexistent and the Savior of Mary and all Christians. He was Mary's Lord as well as Elizabeth's and ours. Jesus was God incarnated into human flesh. Mary gave birth to Jesus, yet, he brought His Godhood with him. He did not get it from her.