Revelations was a metaphorical prediction of the fall of Rome, written as metaphor because Christians could not openly criticize Rome at the time for fear of persecution.

I think it was a metaphorical prediction of the fall of Jerusalem which happened in 70 AD, at the hands of Rome. Revelation speaks of the downfall of the Great Whore Babylon which rode on the Beast. Several times in scripture the unfaithful Jewish religious system was likened to a prostitute, and Nero Caesar was given the nickname of The Beast by his own staff. The Whore riding on the Beast is a picture of the Pharisees and Sadducees getting their power to persecute from the Roman government which enforced their wishes like they did with Christ whom they crucified.

Christ predicted his second coming would occur very soon after his death. He was emphatic in many verses that he and his apostles were already living in the end times, and that various signs of the immnent end of history (emphasis mine) had already come to pass.

Jesus never said anything about the end of history. Neither did anyone else in the Bible. They only spoke of the end of an age, such as the end of the Old Covenant age. That occurred at the destruction of the Temple in 70 AD.

You are arguing against only one paradigm of prophetic interpretation, Futurism. It's easy to poke holes in that one. I poke a few holes in it myself with this post: Wrong Assumptions About the End Times