"...that has survived, yes. Very Happy"
You are so stubborn. Dannyboy ----->

"The expectation of a messiah kind of presupposes the expectation of a new religion, wouldn't you say?"
What makes you say that? I think the evidence is quite plain that at the time, the expectation of a messiah presupposed the expectation of a new Davidic kingdom, and that this kingdom would be global in nature. This is reflected very well in the Suetonius quote:
"There had spread over all the Orient an old and established belief, that it was fated for men coming from Judaea to rule the world"
There isn't a hint of a new religion in that quote.
I think the opposite was actually true: the last thing anyone expected for the messiah was the founding of a new religion. Ask RG. I think he could actually agree with this.
""That he out of all the others that ended up dead at the hands of the Romans was recast as resurrected when none of the others did also requires explanation.""
"*shrug* Sure, religion."
I can't let you get away with being so apathetic about the point. I don't know where you stand but in my conversations with atheists the conspiracy-mongering erupts pretty quickly, asserting that the idea of the messiah being killed and coming back from the dead was a quaint- and common- reaction of an oppressed people.
But in fact, the oppressed people had in mind an idea of a messiah who wouldn't be killed at all, but in fact would usher in a new kingdom.
But more to the point, if you will examine the data, you will see only one of them had this reaction. Isn't that what you see?
Furthermore, if you evaluate what the Christians themselves believed, in the Gospels though Jesus had himself said that he would have to die and then rise, none of this followers believed him and believed to the last that Jesus was going to be a Davidic ruler.
This is a big deal, because if messiah-resurrection-religion founding is common then we may chalk Christianity up as one among many and by your analysis, merely the one that 'won.' But if in fact there were no competitors at all, and beyond there being no religion that formed up by any of them none of them showed much inclination to do any such thing, anyway, then this peculiarity requires explanation, and surely the explanation that it actually happened as described deserves to be on the table.