Never betrayed Him: do you contend that she did? Where is that in the Bible? Her constancy is shown as she was at the foot of the Cross while all but John ran off or betrayed Him (John 19) and at the Pentecost (Acts 1-2).
Who spent more hours at his feet during his ministry? Who was more at risk when Jesus was crucified? Who has more bible ink about him/her. Your observations remind me of some of those football statistics. "Player x is the first 25 year old rookie that was a 3rd round draft to ever go for more than 150 yards on his 2nd game". If you parse fine enough, everyone has some kind of a record.
None of this has anything to do with Jesus reigning through her.
I don't know. Mary is mentioned in the Gospel second after St. Peter, but his record is sort of uneven.
You asked me why veneration of Mary is biblical and I responded. Your next question is Queenship of Mary? Jesus reigns through His Church (Apoc. 5:10) and Mary has a mystical union with His Church (John 19, Apoc. 12). Besides, quite simply, since Jesus is king, that makes Mary His mother queen.