Well Negan not killing Rick would be the comic not the show right? Because as I've read, Rick was there too Negan killed someone else for a reason. But yeah, the shows cliffhanger just killed what could have been there "Red Wedding" equivalent, given the emotional outcry of watching a beloved original character get offed in brutal fashion. It's completely lost now, since viewers have 6 months or so to think about it and know for certainty someone died, not too mention leaks that will inevitably come out once they start shooting.
What would make it even worse is if they choose fucking Aaron or even Eugene lol like anyone would give a shit. But knowing the show, I bet the first, hell maybe even the first couple episodes won't even reveal who died and they'll drag it on by showing each survivor individually, like they'll show Rick and Carl, then segue to Daryl, then Michonne, then Rosita, and finally leaving two characters they haven't revealed yet and finally show whoever died lol you know that's exactly what they're going to do, milk that shit as long as possible lazy bum writers.