You expect Catholics to have a debate based on your terms, so I'm asking you to prove the basis for your foundation. You keep asking for proof in the Scriptures for Catholic beliefs when the basis of your entire argument doesn't exist in the Scriptures either.
Tradition or no, can you give one example of anyone in the Bible appealing in prayer to anyone other than God.
The fervent prayer of a righteous person is very powerful (James 5:16)
I shall continue to rejoice, for I know that this will result in DELIVERANCE FOR ME THROUGH YOUR PRAYERS and support from the Spirit of Jesus Christ (Phil 1:19)
First of all, then, I ask that supplications , prayers, petitions, and thanksgiving be offered for everyone...this is GOOD AND PLEASING to God our savior..." (1 Tim 2: 1-4)
These and more verses show that it is acceptable to ask others to pray for us. These people are secondary intercessors. Since the Church is the Body of Christ, we are, indirectly, asking Christ to help us when we ask others to pray for us. And given that the Body of Christ consists of the saints in heaven (and Mary), we can logically ask the saints to pray for us, with the assumption that they are righteous. (James 5:16)
At your place of worship, do you have altar calls? Do they preach the Word of God? Well, those also are secondary mediators. In each case, a second person is mediating between the person in the pew and Christ. Prayers to the saints asking for help from God is along the same lines. All is done through the virtue of the fact that we are the Body of Christ.
Regards