Most assuredly there is unity in the Body of Christ. She knows no denominations or walls. Therefore, there are believers who attend a CMA church, those who attend a Moravian church, those who attend a Catholic church, those who worship underground in homes, etc. On essentials (i.e., that Jesus is Messiah, that His finished work on the cross saves, original sin, etc. ) delivered by The Christ there is agreement. On non-essentials (eschatological positions, new earth/old earth, whether sign gifts are extant today) there is liberty.
Does that mean there are people who are in the Body but still babies in their understanding of His word? Of course - that's the process of sanctification. (A good example would be Norma McCorvey who trusted Christ, but took more time and feeding on the Word of God to understand His authorship of all life.)
This isn't about Catholicism vs Protestantism. (For, after all, both have erred and not always taught the Word of God.) It's about what God sees - as He looks upon the heart, while man goes about looking to the exterior (the membership, the style, the leader, etc.)
You lady, are my heroine. :-) You certainly are saying what I feel is true, so very well. Cudos.