These are good points, and I am in league with Lorraine Boettner when he says that a certain amount of diversity in the finer points of theology keeps all of us honest. [My paraphrase].
It is a singular mindset to the Romans that there has to be unity in everything ecclesiastical. It’s not necessary to salvation. In the matter of heaven versus hell, all Protestants believe that Christ is the only means of salvation, and the only mediator between God and man. Church government, God’s means of speaking to us, what angels are, etc. are all distinctives without a real difference in the underlying truth of the reality of sin and the need for salvation in Christ. That is my only point. Therefore, that makes the Protestants the real catholics.
That is not completely correct -- Seventh Day Adventists for one, do not agree with that I'd say