Yep Chika would be a top candidate as of now the next would be Ami, I'm sure Ami would go mad if she ever saw sensei banging other girl (specially if it's Maya) with her own eyes
Chika and Ami have the most yandere energy, yeah.
Noriko talks a good game but has been a giant softie wuss every time push has come to shove.
You have a point but Ayane is Ayane we can't really tell if it will be the same for the others
Yandere is my favorite of the dere personality tropes and I've been dealing with characters fitting that trope for a long time, so much so that I did get fooled one time already in this game as definitive signs were shown that turned out to be fake. My analysis in terms of who would be a potential yandere is below, including any character that was mentioned in the comments I replied to whether potential is there or not. Spoilered text is for actual details being given that I could not otherwise avoid in the analysis:
Chika is just the type of girl who takes relationships seriously, the real danger with her is not Chika, but Yumi. I could see her getting angry, not to mention Yumi hunting us down with intent to kill for the rest of the game, but I don't see her going yandere. I don't have a feel for how Chinami would react if her big sister was betrayed, too little time with her. She would obviously be upset and possibly angry, but I again don't see the potential for a yandere in her. I started the game thinking of Ayane as a candidate for going yandere as she was
showing definitive signs that turned out to not be real as of the first beach event, when Kirin walked in on her having sex with Sensei. In fact, the scenes set to be removed involving her were some of those signs, I immediately thought of her as a potential yandere when the
bathroom scene happened as that is something abnormally forward that a yandere would definitely pull, kind of gives me the same vibes as Noriko's
attempt to get Sensei to have some fun with her when she was supposed to be escaping while Maya was distracted. Then there's that
gun she carried around and kept showing off, which was
stated to be a toy in the same scene before the bathroom part. Then came the first invite over events and that's where one of my two current candidates for going yandere came in, Ami. Notice in the first of those events, for every character,
she gets extremely jealous and angry at you, with fire literally in her eyes and everything. Then there's the scene where
she calls out for her parents during sex with Sensei in her maid uniform for her job, which shows she is unstable to a severe degree, likely from the accident that orphaned her (and yes, by definition, she is technically an orphan as the term only counts the real parents). My other candidate is Noriko, who does some pretty crazy stuff early on, definitely traits of a yandere, including
tempting Sensei into sex, and failing, by getting topless when she's supposed to be escaping while Ami distracts Maya, who had come over to Sensei's house. Noriko has also
openly admitted to being armed, though whether this is actually true I don't remember being revealed. This right here is a major red flag for yandere behavior, even more so than Ayane's initial actions and Ami's apparent
instability. Any character that shows a willingness to do potentially dangerous things, such as what Noriko did in the spoiler, for one very specific character or that is shown to be willing to arm themselves, whether true or not does not matter until it is revealed, is a major candidate for being a yandere.
For the reasons above, Ami and Noriko are my current picks for potential yandere.