You will get nowhere debating with Catholics especially in the sub. The downvote train will now commence.
They do not believe...
All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: (2 Timothy 3:16 KJV)
They don't believe that God breathed words contain all we need to know how to please God.
That the man of God may be perfect, thoroughly furnished unto all good works. (2 Timothy 3:16-17 KJV)
When councils of uninspired fallible men vote in conflict with God's inspired they side with men.
Debates go on and on because we do not debate using the same standard, God's inspired word.
You are correct that the Catholic Church started hundreds of years after Christ established His church. You are correct that Catholic church government is patterned after the Roman government. You are correct that there is no authority for any church government above the autonomous local congregations. You are correct about the idolatry. You are correct that there is no authority for popes, rosary beads, or priests dressing in a way to set themselves apart.
In fact here's a passage condemning separatist attire.
But all their works they do for to be seen of men: they make broad their phylacteries, and enlarge the borders of their garments, (Matthew 23:5 KJV)
This passage specifically describes the Catholic Church and condemns it.
Forbidding to marry, and commanding to abstain from meats, which God hath created to be received with thanksgiving of them which believe and know the truth. (1 Timothy 4:3 KJV)
The Catholic Church is not the church the Christ established and 33 A.D. it is not the church that we can read about in the Bible. It does not follow Christ's pattern found in his inspired word.
More information is contained here. This video covers much more. But it does cover the history of how the Catholic Church was formed and how it differs from the Lord's body.