It's always nice to have non-Christians explain to me what the Christian faith and history is. How many Churches did Jesus establish? Have you heard of the apostolic Church of the first millennia? There was only one Church before the Great schism of 1054 and as far as Orthodox Christians are concerned - it still continues to be one, because the Church, being the body of Christ, isn't subject to change and division. Those who seceded and adopted heterodox teachings fell away from the Church - be it Aryans, Manicheans, Nestorians, Gnostics, Muslims, Talmudic jews, Catholics, Protestants, etc.

The comparative approach you adopt assumes any likeness between two religious traditions is due to cultural influence and seeks to prove one originates from another based on this which is a genetic fallacy. It's also a word-concept fallacy because it assumes the same words and symbols used refer to the same or similar concepts and share similar meaning (no, Christ is not a "Sun god" or Sol Invictus, but the Son - the second person of the only God who is Trinity; the greek logos is not the Christian Logos nor is the teaching of the soul; the Egyptian idea of afterlife has nothing to do with the Heavenly Kingdom of God).