Wasn't it announced at E3 2018?
Edit: Ah, it was announced in 2017. My mistake
Nevertheless I do think Three Houses could've used a considerable amount of time in the oven, at the very least to make some of the routes better, or maybe fix up graphics or adjust difficulty in some areas.
I always say the calendar system is less like Persona and more like the Trails of Cold Steel games, since the hub is small and contained, it's not really active daily, but rather weekly, and you have a set number of things you can do in any given day. I kinda feel like people saw the calendar and latched onto Persona because that was the in-thing, heh
I do agree with the monastery's general limited...ness, though I've overlooked it at some points because it's done moderately well to allow me to really fine-tune my units. There is a bit too much around the monastery though, and it absolutely could've been either cut down or more resources could've gone into other aspects of it. Like, I don't think anyone does fishing unless it's that fishing competition month challenge, and I believe people generally use the cafeteria as their weekly activities to raise the motivation of their students, probably with a round of arena in there to get the monthly reward. At the very least I'm glad they added a few more facilities in the DLC, but I kinda wish they did more, you know?
The only really good and useful one is the sauna, most of the facilities in Abyss are kinda just shit. You get the wayseer who honestly is kind of useless and eats up your renown for endings, not to mention she doesn't appear until after she's even remotely useful, because raising bonds with other students, especially those outside your house, would've been useful in the pre-timeskip. You have the stat checker dude, and you have the trash heap which, to its credit, sometimes does have decent things. The only other good facility in Abyss is the shop where you can buy Abyss seals, and the only thing it's really good for is buying Abyss seals.
I kinda wish they'd add more facilities, rather ironically, but only ones that work and have a tangible effect on your gameplay. Maybe a tutor area where you can take a student to the side, raise your support, and raise their proficiency in a subject significantly, or a mock battle area that lets you pit your students against each other, to let you test builds and even strategies in a controlled environment.