It'd be easier to believe in historical Jesus if we actually had something, anything from when he was alive not references written decades after his crucifixion. There is no known contemporary evidence of him and no Tacitus and Josephus aren't it. The gospels as far as we know weren't even written until decades later as well and they took a lot of "inspiration" from older mythologies/stories. Besides, if you want to do a religious figure Moses without evidence would be the correct answer.
Do you require as much contemporary evidence of other ancient historical figures as you require of Jesus? If you do, it might be so that you should stop believing in the existence of several of them too.
The next thing I'm about to say doesn't really relate to what you wrote as it's about the later writings:
I don't understand why some don't want to accept the references for Jesus in the Bible as any sort of evidence towards his existence. People often want to see evidence outside of the Bible. But the thing is that those texts weren't always part of the Bible. So if we could go back in time when the letters and all were unrelated to each other, completely separate things written by different people, would people still say they don't count?
I mean, denying their reliability just because they are in the Bible is basically the same as denying any other collection of writings about some certain person just because they were at some point collected and put together.
So..
For Jesus to be completely fictional person there seems to be awfully lot of mentions about him as a real person. I'd say there are more references about him than some other historical figures whose existence we don't generally doubt.
And by the way, some of the contents of Paul's letters can be traced to comment on situations that happened very close to Jesus' death. So there is contextual connection. It's not a historical accounting of things like the gospels but it's someone writing to letter to someone else and saying something like "hey remember the time when this and that happened, when we were here and there" and those references can be traced back to very close of Jesus' death. So unless there was some elaborate plan to write about something that didn't really happen to just fool people they are casually writing about a person who didn't really exist then there are too many things connected to Jesus' existence to not believe he existed. And if you go to the route of it being this big plan to deceive people, well, all I say is I understand conspiracy theories are interesting things to delve into and good luck to you in your endeavors