Resident gamedesigner-ish guy has read this and now come up with ideas you can steal:
What if the premise of the game revolves around Aya finding herself in a 3-day time loop? And, in order to get to the bottom of the "true route", it involves learning things in the different routes that you can then go back and use in the context of a different route when time resets? The story would start with Aya just wanting to take advantage of the time loop to spy "report" on everyone and get all those juicy stories, but as she becomes more knowledgeable from spending time in the time loop, it eventually leads to her trying to discover the source of the time loop and break it to return things to normality.
Additional gameplay idea, because Aya retains all the information she learns from previous loops, it allows the player to choose to write about any story they've previously learned even if they haven't gone to investigate that particular story in the current loop, leading Aya to be able to manipulate her way into more obscure situations. To help manage all this the player would be able to look at the notes kept in Aya's notebook at any time, keeping track of all kinds of information they have to use.
It would take a lot of careful planning to pull off something like this well but I think it could make a really good detective game.
There's a lot to this idea that I like, and a lot I don't, so I'm a little conflicted on it. I'll start with what I like:
First of all, the main one: the idea that a particular event could play out differently depending on what Aya knows from previous loops is one that I
really like, and it could potentially add a lot of depth to what's already an interesting concept. Additionally, the time loop would give some context to how Aya knows everything she'd need to know to access the true route, and make it a little easier to write. Sure, the
player can put together everything they've learned to deduce what's going on, but without the time loop, how can
Aya do this, when she's never seen most of the events the player has?
Ok, now for what I don't like as much; first of all, it'd probably just be a little hard to implement. This is a relatively minor problem, especially since I've already worked out some of how the logic could work in my head, but it's worth bringing up. Second, it feels like it might make the game a little too... linear? The point with my original idea was that the player can technically access the true route at any time, even on a first playthrough, but due to how difficult it'd be to figure out how to do so, they'd need to do multiple playthroughs to get enough clues to access it. How much information counts as "enough" will be different for everyone, but regardless, the important part is that you're entirely figuring it out yourself. With the time loop story, though, Aya figuring this out for herself becomes more of a scripted story event that can only happen once there are enough cleared events on the player's save file, which I don't really like the idea of. Of course, it's still
possible for the true route to work the same as it does in my idea with the time loop, but "the story would start with Aya just wanting to take advantage of the time loop to spy "report" on everyone and get all those juicy stories, but as she becomes more knowledgeable from spending time in the time loop, it eventually leads to her trying to discover the source of the time loop and break it to return things to normality" gives me the impression there'd be more of an in-game progression outside of the three days, and that progression wouldn't just be something that slowly happens in the player's head.
Regardless, it's still a good idea! Like I said, a lot to like about it, and my issue is more with the specifics than any inherent problem, so if I ever do make this game, I might end up using that. Thanks for the suggestion!