I actually think starting with the murder, while arguably unnecessary, actually worked really well in context and didn't weaken any of the themes. The way it played out, with Comedian's defeated stance, having come to grips with this world without hope, knowing he's outclassed by something awful and beyond him, but…

Wait, why is an android having a psychic aura to read LESS plausible than a human having one?

Yeah, and Jojen Reed would be a perfect match for Marceline. Ageless teenage vampire, meet Little Grandfather.

I'm fairly certain that he was shamed out his relationship with his secretary before anything physical happened. The movie certainly wasn't subtle about anything else so leaving such a big character-defining dick move implied would be out of place. It was still an emotional betrayal but I think that's as far as it…

A lobster? There was more than one lobster present at the birth of Jesus.

Keira Knightley has her own successful franchise where she fights the undead too, you know. It's a match made in the unquiet underworld.