What's the evidence that backs up your scenario?
If you don't wish to type it out again, could you link to where you have presented the evidence before?
OK, so we've got Jesus as a Jew from Nazareth in Galilee. Everyone agrees that's where he was from, it's something nobody would want to invent if it weren't true, and his followers go to some lengths to explain it away, in fact, because it doesn't comport with any messianic prophecy.
That he was from there is overwhelmingly likely.
And this also is our first evidence that he was a real man, not made up for any reason.
There simply are no traditions of a messiah who's a Galilean peasant. And unsurprisingly, there are no known traditions about anybody from Nazareth at all.
The next bit is his association with John the Baptist, who is also described in the writings of Josephus.
John appears to have been a charismatic Jewish holy man who had a mission in the southern wilderness performing baptisms. Immersion and ablution were very common in Judea and Galilee, but John had some sort of twist to it, and was a popular figure.
For some reason, Herod has him jailed and beheaded. According to the Christians, he criticized Herod's marriage, which is actually possible, but who knows.
Anyway, we're confident that Jesus became a follower of John because….
1. His followers agreed that he did, even after the point when they believed him to be a messiah.
2. Jesus was of the same ilk as John and other holy men of that place and time, so it's perfectly reasonable that he would have at one point been a disciple of one of them.
3. Jesus's followers quickly developed stories in which it is explained why Jesus got baptized by John, because it's problematic, seeing as how John should not have had the authority to baptize Jesus if Jesus was who they said he was. Had Jesus not been one of John's followers, and not gotten baptized by him, it's not something that anyone would invent only to have to turn around and make excuses for it.
So here we have this Galilean among John's group, perhaps a student in his inner circle, when John is beheaded.
Well, if you're already apocalyptic -- and these guys weren't the only ones by a long shot, it was a widespread brand of Judaism at the time -- and you think your leader's a prophet, and the state kills him, at a time when the Temple is being run by non-Levites (which is contrary to the Law)… that tends to breed true radicals, absolute believers.
Given what his followers come to say they believe, there is little doubt that Jesus was a truly committed apocalyptic Jew who expected the Day of the Lord to come imminently, during their lives, and for the leaders of the world, including Judea and Galilee, to be obliterated, and for him and his followers to survive and live in paradise.
That fits seamlessly with the stint under John which his followers tell stories about.