A lot of the trash talk about him was made up by Christian historians, I'm pretty sure the "beating his pregnant wife to death" is confirmed, or at the very least heavily debated, to be one of the made up bullshit. And yes, it's generally believed that he is the "beast" from Revelation butt again that's because of the early Christian hate. It's probably because he accused the early Christian sect of causing the fire of Rome (which we're still not sure they didn't), and the whole "throwing them to lions" thing, and they fought back by spreading shit about him.
Marrying a castrated slave lover is legit though, and IINM I think Nero was the one dressed as the bride.