The Roman Catholic church offers a scriptural explanation for its doctrines and traditions but like many, I simply do not see many of them reflected in scripture. It would be intellectually dishonest for me to say I see: Mary Co-Redemptrix, Absolution, Purgatory, repetitious prayers, just to name a few, in scripture. I believe many Roman Catholic doctrines and traditions would be foreign to the Apostles.
Conversely, Sola Scriptura is not the answer to Christian unity and true doctrine, otherwise there would not be thousands of Protestant denominations and independent churches.
Jesus' prayer that His body be one is yet to be answered.
Being Orthodox, I would in general terms agree that Rome comes up short in some areas. But Protestantism, especially of the low church Evangelical/Pentecostal/Dispensationalist variety, is just so deeply divorced from Apostolic Christianity that there is doctrinally very little commonality left. This is one of the reasons I eschew the Prot/Cath flame war threads.
It’s reached the point where they aren’t talking to each other anymore. They aren’t even debating. They are just posting, over and over again, the same (often shallow) recourse to this or that Scriptural verse or Church Father with no real hope of doing anything other than not looking theologically defenseless.
In other words they are just talking past each other and I really am not interested in that. To have a constructive debate you need to have enough in common to be able to agree on the basic ground rules, or authority in this case. Because that doesn’t exist a serious debate between Christians of the (small ‘c’) catholic tradition and the neo-Protestants (as opposed to the old liturgical and credal variety) is all but impossible.