I'd guess Hans Moleman. Since he's already died once before.
Second guess? Bumblebee man. Most likely going to be a joke about the "Major character" thing... and really what purpose does Bumbleebee man serve as being, slightly racist since he's like the only Hispanic guy on the show.
Though if we're talking dark... Think how shocking and insane it would be if it was Maggie. Of course that would never happen... but i'm just a fan of occasionally the most shocking thing happening, if anything just for a scene to shock viewers, then go back to the real thing as a Kaufmanesque joke.








