S-K won't fall. Lofwyr may be full of pride, but he will stop before total defeat, so he can strike again later.
Aztechnology may or may not fall depending on how things go with Ghostwalker and Sirrurg. But I'm not betting on them going away entirely. Just smacked around a bit.
Renraku is up to something, but when they're up to something it usually takes decades for it to finally blow up in their faces. No, they'll likely be ok.
Wuxing, Evo, Shiawase, Mitsuhama, and NeoNET all have internal issues, but nothing critical at the moment. They aren't going away.
No, the only possible choices are Horizon and Ares.
Horizon has bet a lot of their reputation on the Az-Am war, and has been dirty dealing with technomancers, AIs, and free spirits, causing those groups to go into a guerrilla war against them. As the newest of the AAAs, everyone else (from the other AAAs to all those hungry AAs) wants to knock them down a peg, since they're the low hanging fruit of the Corporate Court. Definite problems await them if the techno/AI faction manage to break into the Consensus, like it seems they're going to.
Ares. Oh Ares. The biggest mistake Knight ever made was in rushing the reorganization of Ares following the butchering of Cross. In trying to draw everything under his control, he allowed his rivals to take over significant chunks of his empire. And they intend to fight him every step of the way. Plus, he's under the delusion that bugs can be tamed, and can even be used as weapons. Between massive internal divisions, and the instant global reaction people will have with the headline that Ares is an insect hive, Ares is the one most likely to fall.