I don't agree at all. We all know Episode IV only became such after the massive success of Star Wars, and there was never such foreplanning on Lucas' part.
As for "true" prequels, that's nonsense. They were earlier installments which followed an already-revealed later story. They are prequels. You either watch them in order and accept that Vader's reveal at the end of Empire is not going to surprise the audience (it still works but in a different way) or you watch them in production order.
Anyway, we're clearly not going to agree on this, so good luck with that idea, but I think you're totally wasting your time.