Bart Ehrman destroys Christianity in under 12 minutes.

[Aractus]

And, then, these very early manuscripts were written at least a generation (40 years) after the death of Jesus

No they weren't. I find it near inconceivable that Matthew could have been written to Jewish Christians after the fall of Jerusalem. But let's ignore the gospels for a moment, we have at least two letters of paul that reliably date to 51-54 AD, and the Epistle of James which almost certainly was written before 50AD.

I would agree with you that the Gospels contain some of the words of the historical Jesus, but even scholars themselves cannot agree on which ones Jesus actually spoke!

Incorrect. The Sermon on the Mount is pretty much universally accepted as being genuinely delivered by Jesus, especially given the number of times James makes direct reference to it before any of the Christian gospels were written (he directly cites it something like 14-19 times, in addition to citing other things Jesus said as well). If he didn't give the Parables of the Rich Ruler and the Good Samaritan then it's up to you to prove where they came from, not up to me or others or Christians to prove it. I think that most sceptics would agree that the Parable of the Good Samaritan was one of Jesus's best teachings - if not the best. It was not at all aligned with the conventional wisdom of Judaism in the first century, which is what really makes it interesting.

That said, I don't think he ever claimed to be the Messiah. I'd agree with other sceptics that when Jesus talks about the "Son of Man" he is not referring to himself in the third-person, but rather looking towards the celestial being prophesied by Daniel. Those are great points of difference between us and Christians, but ultimately I'm forward looking, so of course it could one day be shown I'm wrong and that Jesus was referring to himself as the Son of Man - and if that was the case, as a sceptic, I have absolutely no explanation for it.