What will Phase 6 of the MCU look like now
There has been IMHO too much investment in Kang so far. I didn't like the character at all. But this looks like it's past the "point of no return" Building up another major villain will require more ramp in across the different storylines and franchises. You start to radically change the projected timelines and you'll risk losing the more "in demand" actresses/actors already entrenched.
Feige has to understand that he can't lose Florence Pugh. So many of the Phase 4 characters and films didn't work out. Pugh was one of the few that rose past the carnage. Whether it's Kang or a new major villain, it will have to be a POC. The media firestorm to do otherwise is just too much attrition for the currently floundering MCU. If the MCU wants to keep Kang, then recast and try to keep somewhat of the same "tone", then I can see Jordan Peele or Jeffrey Wright being approached.
What would I do as Feige? If you keep Kang, then cast Will Smith. He's never played a bad guy before. He can carry a film with enough of the right components in place. It allows him a "comeback" narrative. You can spin it that Smith hurt someone to defend his wife while Majors hurt someone who wasn't even his wife, etc, etc. I'm not saying I'd buy that myself, but for a marketing campaign, I can see some version of that being deployed.
Alternatively, since Blade is a mess right now, then bring back Wesley Snipe as Blade and make him the main villain. The "thirst" finally got to him. Show him killing Karen Jensen, The Eternals, Shang Chi and most of the Wakanda Forever cast. Basically use him to purge the MCU of all the franchises and characters that don't work.
But this was strategically timed. So the last four months of 2024 are likely ( my best guess/assessment) will likely be nothing but rioting / looting /burning in most of the major cities in America. The switch out from Majors gives a decent sized excuse to push the timelines back some to attempt to avoid that. No one wants to go to the movies and out in public when they see people being burned out and looted night after night near Xmas 2024.
There's only so much you can push back the timelines though before it creates stacking problems for Feige and the practical logistics around pumping out more Avengers films. Sometimes a rose grows out of a cowpie. This is a potential opportunity to "reboot" the MCU and purge it's non viable elements organically if the cards are played right.