oh man, are the showrunners and AMC really dumb enough to just cut to black with Negan and Lucille? That would seriously be the worst. Just because, as others have said, it would be a horrible cliffhanger and completely miss the point what made Negan's introduction so memorable in the comics.
To me, Negan's introduction from the comics sticks with me for a couple reasons. Its brutal and right in your face. Glenn gets his head caved in way up close in those panels and its hard to look at. Combined with him screaming out for Maggie and its gutwrenching. Then you add in the fact that Glenn is one of the original survivors and its even more of a shock. And all of that shows you that Negan isn't messing around.
If the show just has it end as a cliffhanger, instead of it being a super memorable gutpunch it'll likely just get spoiled when they start filming again. And if it's just Aaron that gets Lucilled? I like Aaron but he's barely been in the second half of this season. Negan needs to kill an original cast member, not another Alexandrian.