I've actually written the initial role for this character, but it's been years and I know I'll never end up doing it so I might as well share.

The idea is that you're a charming bartender by day, and a hired killer by night. You take contracts in advance, and meticulously stalk them. You ONLY try to assassinate, fleeing quickly if anything goes wrong and always feigning ignorance if called out on it. You pre-pen a note with a fun/interesting poem about the character and place it down by their corpse when you kill them. It's your true artistic expression, and the herald part is a fun distraction and a front. The character was going to be neutral and not necessarily delight in killing, instead thinking of it as a key aspect of the world that should also be celebrated in some way.

I think it would be a character that added a lot of intrigue, and improved the game for everyone involved.