I guess I'll add a bit on Kouseki.

He's quiet with an intense and intimidating glare, he appears to be rather serious as a person but that isn't the case, he can crack jokes though rarely laughs, and does like things you might expect boys his age might like, such as comics, games, and all that kind of thing. There doesn't seem to be a set preference, but he seems rather fond of battles series usually.

He prefers to keep to himself and mind his own business, so it's probably naturally he may not come into conflict with many in his class or even other classes. He's also the type to get rather serious about seemingly trivial things. Due to this behavior he most certainly has a lone wolf vibe.

He's a person who has internalized his own path already, having resolved to do that after leaving his family. Much of his struggle will be choosing between fighting for hero society today, or not. He disagrees with a lot of what has made society what it is today, from hierarchies within the major families, to the commercialization of good deeds and enforcement. He feels it devalues greatly from the idea of a hero, though recognizes that in today's society, "hero" may be synonymous with "law enforcement" also. If the idea of a hero is not that today, then what does one call the idea of good deeds and saving people out of altruism today?

Far as what he might think of his classmates...

[list][*][b]Himura Amaya[/b] - They haven't had any problems.
[*][b]Shenika Kira[/b] - Confusing person, but she has admirable will.
[*][b]Hachi Aoi[/b] - She's kept to herself too so he can't complain.
[*][b]Chinatsu Todoroki[/b] - It's hard to believe they're related. She seems out of place. Is she here to be a hero, or to be saved by one?
[*][b]Anna Costello[/b] - Probably the most normal person in class, not a bad thing to him by any means. He can admire the optimism too.
[*][b]Shiroko Sekkei[/b] - In spite of her appearance, she's probably the most personable person in class. He feels no sense of confrontation from her, so he doesn't feel like he has to be alert when it's just her. Is it because she doesn't want anyone to expect anything of her?
[*][b]Phoebe Carmichael[/b] - He's indifferent now, but unlike her he values the idea of good deeds. Things will change drastically once he finds out her ideals.
[*][b]Tanegashima Kaguya[/b] - "So cool", was generally his initial reaction to finding out about her powers. It may not be uncommon to find him, Kaguya, and Sasuke talking about new tech.
[*][b]Todoroki Hasaki[/b] - Gravely dislikes how he treats battle, not to mention the lack of humility. It's weird how Kouseki were he born with a more suitable quirk for his family he might've been more lenient with Hasaki.
[*][b]Kishimoto Sasuke[/b] - It's unusual for anyone who has a quirk to make so much use of technology, this trait in Kouseki has led him to be able to talk with Sasuke on things like that. Not to mention there's not many other skilled martial artists in the school, or their class for that matter.[/list]