Once more, you are confusing the myth with the man. If the early church existed, and you say you are not denying it did, then it would have been populated with the contemporaries of Jesus. So what you seem to be arguing now is that people who would have known whether he existed - first hand - were actually fooled into thinking he existed through some conspiracy. I honestly don't understand how you can come to that conclusion.
Not necessarily.
The early church DID exist in the 2nd century, but by that time, anyone who knew Jesus was dead and buried.
Most of what we know about Jesus was written by people who had never met him personally. For instance, St. Paul is the first person to write anything about Jesus, but never met him personally. It is equally possible that Jesus was a literary device Paul (or Saul of Tarses) made up.
So here's a more plausible theory. Saul of Tarses has a whacky new idea for Judaism, so he writes about this fellow named Jesus who is a paragon of all virtues. (Unlike Saul himself, who was just another Pharisee dick.) And he wanders around Asia minor telling tales, which of course, borrow from Mithras and Sarapis and all the other God-men of the time.
The problem with the "Early Church" is that you had a lot of different groups that believed different things- Arians, Monophysites, Gnostics, etc.
What we don't have evidence for is a flesh and blood man at the center of all these beliefs. We have a lot of stories, just like we have a lot of stories about Robin Hood, Paul Bunyon and other legendary characters.
An interesting tidbit.. The Emperor Hadrian visited the east in the middle of the second century and remarked as follows....
'Egypt, which you commended to me, my dearest Servianus, I have found to be wholly fickle and inconsistent, and continually wafted about by every breath of fame. The worshipers of Serapis (here) are called Christians, and those who are devoted to the god Serapis (I find), call themselves Bishops of Christ.'