If this game is seriously going to be made we shouldn't follow the ideas of Yandere Similator too closely. Take a few unique twists and discourage killing people as
@Catgirls are Love points out that should make things much more difficult. Nonviolent methods should be your tools; bullying, blackmail, pairing people together, framing people, find useful idiots, etc. The final rival should be another Yandere.
What I do like from yandere similator: clubs and classes giving you extra bonuses, reputation system,
some easter eggs (and make them a mystery), and infochan offering tips and info on the students. But to avoid just taking pictures of all the students and then restarting the game the attributes of the students should be randomized.
I would replace gaming club with computer club to make it more general. The bonus from being in the computer club should be a tech wizard. In some schools they have filtering to block access to social media websites like youtube, facebook, etc. The attribute you get from the computer club is the ability to get access to blocked websites and can spend your time spreading misinformation and posting embarrassing misinformation on your rivals. Posting embarrassing videos and pictures you took of students. Computer club = hacking is too cliche. Lets go with something more mundane.
As for easter eggs, we should have one of the guys in the computer club talk about how he is making a really popular game and would have it finished sooner if it weren't for those meddling emails. Chris-chan and sonichu is obligatory to be added.