Awesome / Bloom Into You

• The fact that Touko managed to change herself from a relatively ordinary girl to the Student Council President, the top student in her grade and a good athlete. As Yuu points out (see below), Touko earned her success through a great deal of hard work. Even better, it's shown that Touko actually lives up to her reputation of being a good Student Council President, unlike her sister.
• Touko's graceful rejection of her suitor in the first chapter, in which she honestly tells him not to put himself down, and truthfully says she doesn't intend to go out with anyone, leaving a strong impression on Yuu in the process.
• When Sayaka sees her ex-girlfriend again, it quickly becomes clear that the older girl still thinks homosexuality is just a phase, much to Sayaka's dismay. Sayaka handles her senpai quite stylishly, reassuring the older girl that she doesn't know how she fell for her in the first place, then leaves arm-in-arm with Touko after calling her by her first name^note Granted, Sayaka and Touko are best friends, so First-Name Basis isn't all that unusual, but Sayaka's senpai doesn't know that. All this subtly expresses that Sayaka's still a lesbian, and the only thing that's changed is that she's gotten over her feelings for her senpai.
• The student council takes third place in the sports festival's relay race, which is quite impressive when you consider that the basketball club (and presumably other sports teams) are participating).
• Yuu's You Are Better Than You Think You Are speech to Touko in Chapter 28, in which she tells Touko that everyone who cares about Touko isn't thinking of her sister, and that everything Touko achieved is the result of her own efforts. Yuu hadn't quite figured out what to say to Touko the last time this came up, in Chapter 10, but this time, she's found out what Touko needs to hear, and actually gets through to Touko.
• The fact that five members of the student council were able to put on a successful School Play with only a few months of practice and no prior experience, and even managed to relearn a significant portion of the play after a last-minute change to the ending.
• Sayaka's Love Confession is awesome as well as heartwarming, proving that she loves Touko as a person rather than as an idol of the school.
• Similarly, Yuu and Touko's confessions to each other in Chapter 40 not only demonstrate their love for each other, but how much they've grown since the start of the series. Touko has outgrown her belief that loving someone requires that person to remain unchanging, while Yuu stops romanticizing love and manages to make one of the most important decisions of her life.
• In Chapter 42, Sayaka finally manages to dethrone Touko as top student in their grade.
• In the final chapter, Koyomi, who'd been working to better her writing skills throughout the series, finally gets a book published. While she's understandably worried about how it will turn out, she isn't resting on her laurels, but is already writing the sequel.

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