The Bible doesn't say anything about Mary being the "ark of the new covenant", in fact the Bible doesn't mention Mary at all in the context of the new covenant. It's a covenant between God and His people, not between God and Mary or God and Mary and the people.
The ark in the old covenant is a type of Mary! Pure and Holy, She is also the new eve, and God required Her consent to be the mother of God and the mother of our salvation! Lk 1:38
If Mary didn't have the original sin then Jesus didn't have to die for us. Mary could've died on the cross then. There is no single verse in the Bible that would indicate that Mary didn't have the original sin, which is impossible anyway because she was born naturally.
we still have original sin and need salvation! Jesus Christ is the only mediator and the only savior!
None of the verses you quoted indicate anything about Mary's "holiness". In fact Jesus Himself said to Mary: "
Woman, what have I to do with thee?"
Jesus is refreshing His listeners memory, gen 3:15 I will put enmity thee and “the woman” this is writ large in rev 12 “the woman” clothed with the sun! That represents her holiness, and rev 11 speaks of the ark of the old covenant.
Joshua 6:19
But all the silver, and gold, and vessels of brass and iron, are consecrated unto the Lord: they shall come into the treasury of the Lord.
Isaiah
6:3
And one cried unto another, and said, Holy, holy, holy, is the Lord of hosts: the whole earth is full of his glory.
She had to be pure and Holy!