It was definitely a good move to have these three chapters released at once. On their own they would be rather lacking, but bundled together they draw a nice line through the series and the relationships that developed. Shiramine using the side-couples experiences as a mirror to her own actions throughout the manga might be rather cliche, but it is very well done and appreciated.
I can tell that some of these responses were more intended as "the public image" rather than just coming straight out with it, so I can forgive that not all of them just said they are a couple. Mizuki and Moe have no need for definitions or fancy words, they are just meant for each other and know it.
Honestly I was surprised to realize that Sawa still didn't think of them as a couple though. It's good that this was resolved here! In the end you cannot measure love, so there is no comparison to be made. In that sense Shiramine's questioning actively helped a couple out too, so at the very least for that, this introspection was worth it.
Chiharu was as suave as always about it, much appreciated. Mikaze and Asuka are the most experienced couple for a reason as well, showing that they are past the "gotta hide it" stage.
Now the only thing I take issue with is Towako and Yukina. This is something I already felt during their own arc, but they really never resolved their feelings well. They are far too stuck in their master and servant dynamic, metaphorically speaking. They are just not on eye-level and it will take a while for them to truly overcome that.
Haine and Aika is a case where I'm most thankful for the ambiguity. Sure, they obviously overstep all the lines of what a normal "family" is like, but overtly going for the romantic option would create a lot of conflict which is just unecessary. Sometimes a relationship has to be ambiguous to work.
Although the conclusion was apparent to everyone, for Shiramine this was quite a bit of work. Just as she said herself, she had wasted most of her school life on being competitive and agonizing over her mother. She is behind in the social understanding department, ironically more than Kurosawa, who learned to be a social person from her hahaha
Looking forward to Kurosawa's surprise. Who knows? It might even be a white lily and kiss for her dearest girl~