Reasonable concern is making me cautious of responding. Perhaps I'm in the early stages of becoming a grumpy old man, but aren't you the "Orthodox" Christian who doubts the existence of souls (as though this is 'optional')? What does "Orthodox" mean? Do you belong to the Orthodox Church like my boys belong to their soccer club? What is Antioch teaching you people?

You and I have completely different "phronema". I'm not sure that dialogue is possible between us. But in answer to your questions:
But don't you think it's possible that Hinduism, Buddhism, Zoroastrianism, etc. were originally revelations from God which simply became corrupted over time?
Not at all. They are a mockery of God concocted by the father of lies. Some see in the "trinitarian view" of the deities of some religions (for example, the Hindu trinity of Brahma, Visnu and Shiva) a reflection of the Holy Trinity and say that this is evidence of divine revelation. On the contrary, this is evidence of demonic revelation- the demons also know that God is a Trinity.
.....or the view which I like better: all religions (with the possible exceptions of Islam and Mormonism) are the "fleshing out" of Jungian archetypes planted in the mind by God. Though, we with our frail minds, cannot flesh them out properly without aid from God....which is where the Burning Bush and the Gospel come in.
Firstly, why do you exclude Islam and Mormonism, and yet include Orthodox Christianity in your "Jungian" view of "all religions"?
Secondly, as I have stated before, God is Absolute Truth, and since Absolute Truth is not relative truth, the only way we can know anything about Him is if He reveals Himself to us. If God revealed Himself by "implanting Jungian Archtypes in our minds" then He would be only a
relative truth, not an
Absolute Truth. This is the very reason God forbad idolatry in the Second Commandment of the decalogue. Rather than me rehashing this point, check it out in this thread:
http://www.orthodoxchristianity.net/newboard/index.php/topic,4459.msg75926.html#msg75926 When I studied genetics at university, I thought that genetics had all the answers, when I studied psychology, I thought that psychology had all the answers, when I studied sociology, I thought that sociology had all the answers.....do you see where I'm going with this?

Put down
"Synchronicity" and
"Undiscovered Self with Symbols and The Interpretation of Dreams", stop making an idol of the "Self", light the vigil lamp in front of your Icons, pick up
"The Orthodox Study Bible" and read.