You reject the Gospel accounts as historical. I think that Josephus and Tacitus(contemporary historians of the day) both allude to Jesus. I do not think there are that many written accounts of the period which survive.
My main support for truthfulness of the Gospel accounts is that all of the Apostle's but John (and a lot of other believers as well) were willing to go to their deaths proclaiming them as true rather than recant. If these accounts were fabricated, the Apostle's would have known it. Yet, they died as martyrs.
As to the "blood was not taken to the altar until Jesus ascended into heaven" argument, I concede that this is a bit of theological exposition I read from a scholar, it is not directly stated in the Bible. But it makes sense to me.
I agree that Revelation is clouded with imagery that is difficult to decipher, but I think certain images can be reliably understood. Certainly, it makes sense to see Jesus as the Lion of the tribe of Judah, the one who can open the scroll, etc. The fact that the lion turns out to be a lamb coincides with John's Gospel where Jesus is identifed as the lamb of God. I believe that John wrote both his gospel and Revelations, so the imagery ties together nicely.
Actually I dont reject them as historical. I think that they are very likely accurate. When it comes to certain details, I am unsure, like the mass resurrection from the dead at the crucification. I cant say for sure whether or not that happened but to my knowlege there is no record of it in Jewish or secular sources. I find that a bit odd since that would have been a really big deal. And what happened to the mass of ressurected personages? Did they live to die again? Did any of them record their experiences? Things like that. But, these are a mere curiosity for me since the big question is, who is G-d? What does he expect from us? Again, I highly recommend, www.outreachjudaism.org .