The fact is, there is no good evidence such a man as Jesus of the bible existed, and some pretty convincing evidence he didn't. Number one, to accept biblical epistles and scriptures as literally true is to accept that magical events happen, and that people can do magic..which is a tall claim indeed. If one is to discount all the unrealistic fantasy attached to the myth, the question of where to draw the line becomes paramount..how can you know, realizing it can't ALL be true, what elements of it MIGHT be true? We might as well start claiming a historical thor that didn't really have a magic hammer, but still fought frost giants(big swedish oafs?).
Also, the parallels between 'gospel jesus' and a plethora of other god man myths itself builds a case for a mythical jesus, unless you want to start wearing blinders and use the word 'co-incidence' a lot.
The problem with your argument is that Jesus wasn't unique in the fact that mythical elements were added later on to his life. We see this with Augustus, where there is no doubt he existed, as well as for Alexander the Great. They both have unrealistic fantasy attached to them. We have no problem removing it from those figures, and we have sound historical means to do so.
Paul also had the same sort of mythical ideas attached to him, yet there is no doubt he existed. So I really don't understand the problem with mythical ideas being attributed to Jesus when it was a fairly common thing.
And no, he really doesn't resemble another "god-man." At least not any more than someone like Augustus does. I wrote more on that here:
http://www.religiousforums.com/forum/religious-debates/110449-jesus-mythical-god-men.html The idea that Jesus resembled other god-men really only happens when people are either very vague, make things up about Jesus (such as him being born on December 25th), or people attributing really late ideas (or made up ones), to ancient gods.
And on the other side, what do we have to verify 'him'? A few mentions of a messianic cult (nobody is claiming paul didn't exist) a generation later, some of which are highly dubious (such as sections of antiquities), and a few passing references to the central element of this cult, the christ. Hell, even paul spoke of jesus in spiritual terms rather than physical, to those that read the bible with a careful eye. And let us not forget the the gospels were written well after paul wrote his epistles and started his cult, not vice versa.
So is it a 'conspiracy' theory, or an observation inconvenient to those that place all their chips, as it were, on the historicity of such a person to buttress their entire worldview?
We have the Gospels, Paul, and Josephus. Josephus in fact is good enough. Paul is more than good enough. And there is no reason to dismiss the Gospels, unless we want to dismiss the ancient biographies of Alexander the Great or Augustus. Especially when considering that the biographies we have of Alexander the Great are from long after he was dead. That is not surprising at all, considering the historical context.
Paul did not speak about Jesus in just spiritual terms. Someone with a careful eye would see that. Paul states that Jesus was born according to the flesh, born of a woman, was a descendant of David, was a fellow kinsman (as in Jew), was crucified, was buried, had a brother and disciples that were still living (as in he met them), had other family that was still living, etc. I wrote more on that here:
http://www.religiousforums.com/forum/general-religious-debates/107542-paul-jesus.html
And most scholars (nearly all anymore) agree that Josephus wrote about Jesus. There are two passages in Josephus, and the shorter one is nearly universally accepted as authentic. The longer one is agree to be partially authentic. I have an argument here:
http://www.religiousforums.com/forum/general-religious-debates/107541-josephus-jesus.html
So it may not be a conspiracy theory to deny that Jesus existed, but it is special pleading, and usually based off of bad research (not saying your research is bad, but the information that you get is bad and is not based on sound scholarship).