I disagree that Mary deserves, or should be assigned, the title of “Queen”.
But that is because I believe you put too much emphasis on Mary as the Mother of the King.
Jesus as Man was not King. It was Jesus as God that is King (I bet I’m going to get into trouble for making that distinction, and I’m not trying to make too much emphasis on it).
Jesus said “my Kingdom is not of this world”.
Mary was chosen by God to be the Mother of Jesus, but there is no indication he was chosen to be the Queen of anything.
The three traditional offices assigned to Jesus by the early Church Fathers are: prophet, priest, and king.
He is prophet because He speaks God’s Word and Truth; indeed, He says that He is the Truth, and He is also traditionally called the Logos or Word (see the opening verse of John).
He is priest because He plays the essential role of any priest: mediating between God and man.
He is King, because God has given him “all power in heaven and on earth.”
This is simply not true, Charles. You may not acknowledge the significance of Church authority, or scripture passages such as the wedding feast at Cana, and the woman of Revelation 12...but these things are FAR from "no indication."
As well you should. At all times, Jesus was wholly man and wholly God. And He is King, both as man AND God. On earth, he hadn't "come into his kingdom" (think Aragorn in "Lord of the Rings")
"Jesus said “my Kingdom is not of this world”."
Correct.
"Mary was chosen by God to be the Mother of Jesus, but there is no indication she was chosen to be the Queen of anything."
She was chosen to be "mother of the King". I've given you the Biblical and historical logic behind the belief. You can certainly ignore it. Protestants believe a lot of things that have far less Biblical support and ignore things that have far more (like the "Real Presence" doctrine).