I understand your premise. Your thinking is not a Catholic one. It is well established that God in His great love and mercy provided a means of salvation which was the blood of His Son. We then must make the choice to believe in that event so that we can be saved.
Romans 10:9 says..............
"because, if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved."
That then by your own admission removes child/baby water baptism as a means of salvation because they have NOT chosen/believed in Christ and certainly have not confessed Christ.
Then as far as Mary being involved in redemption of men, that is solely a Catholic teaching and once again it is not Biblical.
It does not take much study to realize what God has said in Psalm 117.........
“Praise the Lord, all nations; laud Him, all peoples, for His loving-kindness is great toward us, and the truth of the Lord is everlasting. Praise the Lord.”
Psalm 118........
“Give thanks to the Lord for He is good. For His loving-kindness is everlasting. O let Israel say, ‘His loving-kindness is everlasting.’ O let the house of Aaron say, ‘His loving-kindness is everlasting.’ O let those who fear the Lord say, ‘His loving-kindness is everlasting.’“
I find it impossible to believe that any RCC believer can not see and understand that The Roman Catholic view of Mary calls into question the compassion, the sympathy, the loving-kindness of God. It places in the people’s minds doubt about God’s care, concern, sympathy, compassion, and interest in their plight.
Nothing could be further from the truth. The Bible ends in the 22nd chapter of Revelation with John having heard the amazing revelations, and in this particular case from an angel, when he heard, verse 8 of Revelation 22, it says.............
“I fell down to worship at the feet of the angel who showed me these things. And he said to me, ‘Do not do that/ I am a fellow servant of yours and of your brethren, the prophets, and of those who heed the words of this book. Worship God.’“
In another scene in the book of Revelation there is an angel, an everlasting, flying through heaven with an everlasting message, “Worship God. Worship God,” who is to be worshiped as our Redeemer, our Benefactor, our Comforter, our Sympathizer, our Deliverer.
Never, ever anywhere is there is suggestion of Mary being involved in any what so ever!
The Catholic view of Mary is that they/you teach that Mary is the Co-Mediatrix. That is, along with Jesus she is the mediator of all graces. She is the channel of all graces.
I am sure that you remember statements made like this ........
“Mary is the mother of all graces."
"Mary is the source of all mercies".
"No grace is conferred on anyone without her mediation, and intercession, and cooperation."
"All graces come to us through Mary’s hands."
"Mary is the direct intercessor with Christ who receives from Christ all graces and dispenses them to us, and therefore our prayers should be directed at Mary.”
All of that, of course, is lies and deception, and again strikes a blow at the nature of God as one who is loving, kind, compassionate, sympathetic, and caring. It strikes a blow against the mediatorship of the Lord Jesus Christ, who is the only one we need to go to be taken directly to the Father.
Mary IS NOT A Co-Redemptrix, as the Roman Catholic Church says, and this was one of John Paul II’s big issues. I quote from him..........
“Mary participates in our redemption.”
And, of course, he is borrowing language from Pius XI who said......
“Mary participates in the redemption achieved by her Son and all graces are granted only through her intercession. She participated with Jesus Christ in the very painful act of redemption.”
They have Mary in her pain giving up her Son, participating in some form in our redemption so that Christ is not the one mediator, nor is He the one and only Redeemer.
That theology is exactly the opposite of what the Scriptures actually do say.
1 Timothy 2:5 ..............
"For there is one God, and one mediator also between God and men, the man Christ Jesus".
John 14:13......
“‘Whatever you ask,’ Jesus said, ‘in My name that will I do that the Father may be glorified in the Son.’“