These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The second half of OVA episode 1 may qualify as well. It is a nice subversion of the usual My-Beloved-is-So-Flawed cliche, as Sachiko sees right through her cousins' attempts to denigrate Yumi and is not shy about her disgust.
Ensemble Darkhorse: Sei, the original Rosa Gigantea, struck as one of the most popular characters at first for being the most notable lesbian of the show. In latest seasons, Noriko seems to have gained plenty of popularity. The White Rose Family can be considered the Ensemble Dark Horse Family as it is the most popular family in the fandom despite getting considerable less screen time than the red and even the yellow one,
Family Unfriendly Aesop: The message of Mifuyu's story appears to be: "Accept that other people are more special than you."
The message of Sei's backstory seems to be: "Societal obligations will sometimes keep you from someone you love. Learn to accept it."
And both are messages that, while regrettable, are still prevalent in Japanese cultural mores.
Memetic Mutation: This series is responsible for the word "Gokigenyo" being known among anime fans.
Or Kanako, who has a troubled past and isn't shown to have many friends. And who also seemed to be a serious candidate for becoming Yumi's soer, only to get jilted.