I find that the relationship between Yuzu and Mei is not really a backward development, but rather a forward, maturing development. When Mei told Matsuri about starting over to respect Yuzu, she did exactly that. For us who used to see the lovey dovey scenes in Citrus, the interaction between Mei and Yuzu feels cold or odd or "business like". But it is a book separation between personal and non personal (business) lives. They both knew it, otherwise Yuzu would never think of becoming a teacher, or dealing with Arata but without crossing the boundaries implied by Mei. (Its business) The color picture about the two's domestic and daily lives show that indeed the love is still pretty much there. T he only time Yuzu has a problem is concerning Arata and Mei at the beginning but that is understandable because of the trauma she suffered when Mei left her for the engagement with the cafe manager.
I actually like the new characters in C+. They serve well for our understanding of Yuzu and Mei's relationship. At the very beginning Sayaka and Miyabi openly talked about the rumors (or open secrets) about Yuzu and Mei's relationship directly behind Mei and Hmeko's back. Himeko scolded them but that did not stop Sayaka's belief and her plan of blackmail. Yuzu and Mei seem to have a don't ask don't tell attitude towards their relationship. Mei outed herself with Yuzu in the BoD meeting. Nobody objected and demanded that she must marry a husband afterwards. Yuzu then outed herself about Mei and her in the same meeting with more details. The board found it amusing. No doubt the minutes of the meeting would float around people who are related to the board, and I would not be surprised Arata, who is not on the board, heard about it, after all he already knows about Mei's nickname given by the BoD.
Yuzu outed herself (and Mei) to Sayaka (in front of the cafe manager no less).
Yuzu and Mei outed themselves to the two middle school ex-homophobes friends.
I think Arata is a very important character in C+. He probably knew a lot of stuff but has little power to utilize the info. He probably know a lot of powerful people. It is entirely possible that he already suspects or knows that Yuzu and Mei is a couple based on what he heard (from his family, other powerful families, rumors). It is also possible that Yuzu outed herself to Arata off scene because Arata clearly indicated to Mei that he and Yuzu has struck up a friendship and have communicated multiple times. Finally, Mei outed herself to Arata in the exhibition hall. Arata looks surprised (twice). You can interpreted that it was at that moment that he realized that Mei and Yuzu is a couple. But I rather interpret that he already knows the relationship, hence he was able to ask Mei that question about how Mei and Yuzu managed to form a strong force together to achieve goals. I am sure he was not expecting the answer to be "because we are sisters". Rather he is surprised and confused that "love is that powerful".
Unlike others, Arata is now a wildcard. I hope sensei will give him more surprised role in the story, in bombshell fashion.
Instead of thinking that the sensei has running out of ideas for C+, I think it is the other way around. I think she has too many ideas but does not know how to put them in because right now the time line has less than half a year left before graduation. The biggest problem is Harumin's story of course.
It is interesting that Sensei has assigned a second year student as the successor to the student council president as opposed to Sayaka. Sensei drew the character, did not bother drawing the face and did not bother to give a name. I think she is absolutely determined to end C+ at graduation and we may have a bunch of loose strings. Sayaka and Miyabi represents continuation of the story.
As for as Shirapon is concerned, she may have been married by now.
The last panel of Oct 27 I find it very interesting. I have NEVER seen Mei smiles like that. No blushing, This is a smile of someone who is deeply deeply in love. Very significant if you think about it, including the whole panel. "Strength".