*** It is not contradictory to the existing scriptural evidence,***
Here are the verses I find it to be in conflict with. If you know these already please forgive the repetition...
1 Timothy 2:5
"For there is one God, and one mediator between God and men, the man Christ Jesus;"
1 John 2:1
"My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous:"
Hebrews 7:25
"Wherefore he (Jesus) is able also to save them to the uttermost that come unto God by him, seeing he ever liveth to make intercession for them."
Romans 8:34
"Who is he that condemneth? It is Christ that died, yea rather, that is risen again, who is even at the right hand of God, who also maketh intercession for us."
BTW, than you for the civil tone. These conversations always get so heated.
The Catholic belief is that Christ alone is the judge of our salvation. Indeed, there is clear scriptural teaching that that is so, as your quotes demonstrate.
Intercession is not scripturally claimed to be Christ's alone. We see Blessed Virgin Mary asking Jesus to perform a miracle at Cana, which begins his ministry as a worker of miracles. We see Mary of Bethany and Martha asking Jesus to raise Lazarus, -- the miracle clearly prefiguring salvation of men, -- and even rebuking Him for tardiness. In the Old Testament Abraham pleads with God. Thus not only intercession of the Blessed Mother, but intercession of saints in general are scripturally sound.
Catholics tend to get angry when they are told that they don't read the Bible, or that they repeat what the Popes tell them, or that they do not worship Jesus, etc. Anger is not the best reaction to have, all the more so since the devotion to the study of the scripture is an admirable Protestant trait. Nevertheless, understand that when one's faith, particularly a demanding faith such as Catholicism, is questioned in a rude and ill-informed way, a foundation of one's existence is attacked, and people get very defensive.