There is a reason I keep returning to this movie. Killmonger is perhaps the best villain presented by a comic franchise. Quick, tell me why these guys showed up to wreck shit: Steppenwolf, Ultron, Green Goblin, etc...
Their backstory was SHIT compared to Killmonger's. He's, in my estimation, the greatest villain because he's so goddamned sympathetic. His claim is undeniable and you have to hate T'Challa's daddy for abandoning the kid. Plus Killmonger is a certified badass.
If Killmonger stays dead (not something I think anyone can assume about these characters), then I think the MCU is poorer for it. That's gonna be the guy that knocks Thanos for a loop.