I will just skip on down. The net result must be that the Roman Catholic Church:
1. claims authority based upon the Bible,
2. of which parts may not even be the Word of God, but
3. which it alone is capable of interpreting.
Got it.
I am not sure why you mention the Roman Catholic Church, but since you mentioned it, the RCC claims authority based on the Bible (which the members of the Church wrote and chose), and the Apostolic tradition, reorganizing that not everything the early Church believed is written in the Bible. The interpretation is based on the collective interpretations of the early Christian apologists who wrote in the cultural and linguistic milieu that produced the Bible.
The Protestants base their interpretation on literal reading of the Bible translations (most of them faulty or doctrinally "doctored"), and in the cultural milieu far removed from anything even close to the linguistic or cultural atmosphere and values of the 1st century Middle East—individually as the "church of one", and as each man or woman his or her own pope (and magisterium).
As for its treatment of various parts of the Bible, the Catholic is based on the Gospels (not on Paul, as some claim), and the Gospels are the only scripture sitting on the altar. When Pauline Epistles are read, it is read by laymen, and the congregation sits. When the Gospels are read, they are read by ordained individuals (deacons, priests, bishops), and the congregation stands.
Despite the RCC's lip service (forced by the Reformation)that all scripture is "God's word", the Catholic Church (both east and west) doesn't treat all parts of the scriptures equally.