I think most of the “corruptions” are of such minimal consequence that they fall under the “don’t get into useless disputations” clause that the apostle Paul warned us not to fall into.
Christ is God in flesh, born of the virgin Mary, killed, resurrected and now is an advocate for us with the Father! He died to cleanse us from sin and to restore us to fellowship with the Father. Though the serpent bruised his heel, Christ has crushed the serpent’s head! Christ delivered the truth of himself and the gospel to the apostles as he was the chief cornerstone thru which the apostles built the Church via the Holy Spirit. Christ will again come back to destroy the works of the devil completely and to claim his own, both those then living, and those dead in his name. We are urged to confess Christ with our mouths and to believe that God has raised him from the dead in our hearts in order to be saved; and then, having done so, to be baptized in his name. We are also urged to preach the gospel to every creature, where we may...in our immediate surroundings and unto the far flung parts of the Earth!
There lies the basic Orthodoxy of the faith,,,more or less as any simple man can understand it! The rest is semantics and slantings of the various teachers and preachers, most of which are pretty decent, no matter what denominational persuasion.
I'm glad for you that has been your experience. It hadn't been mine in mainstream protestantism.
Amen to the rest of your post. I believe in unity and fellowship among Christians, not sectarian squabbling. That said, when a denomination goes off course, sooner or late the faithful leave. That is why the old mainstream churches that once were huge are now struggling; yet the liberals in charge won't admit it and change course. They are children of the Father of Lies whose purpose was to destroy those churches, and to a large extent they have succeeded. But, as I said, the faithful have left, so all they can do is destroy the remains of an organizaton.