So was Aaron's rod that budded. I don't see your point. The ark contained a record of God's redemption of Israel. The items themselves were not holy. They only had significance insofar as they were used by God to redeem His people.
This is in a culture which washed ritually for every meal!
Which Jesus condemned as a human tradition. (Mark. 7:3ff).
This is why Gabriel called her "full of grace." She was sinless as the prospective Mother of God should be....
Only according to RC theology. It ain't in the Bible. The same word is used in Eph. 1:6 to refer to all followers of Christ.
Incorrect. The words in Ephesians are thV caritoV autou - "the grace of Him" - meaning Jesus - believers are sanctified through HIS grace. The noun form is used.
The word in Luke 1:28 is kecaritwmenh - a very specific verb form (perfect/passive participle) that you can translate as "is and has been 'graced'." "Full of grace" does omit the passive aspect of the verb form indicating that the grace proceeds from God, but it's as close as we can get in English which doesn't have the precision of Greek.
The word appears nowhere else in the Bible. The Archangel did indeed give Mary a unique greeting for a unique person - the one who consented and was prepared to be the mother of God incarnate.