I think I finished School Days staying fully on the Kotonoha route. Looks like nobody knew Sekai and Makoto weren't dating for some strange reason, but it was okay. I thought Sekai would've ended up commiting suicide or something harsh, but in the end it looks like she got over Makoto being with Kotonoha. It was a bit sad for her since she began caring about Makoto's happiness until she noticed that her efforts to help him ended up distancing them, but I felt she somewhat deserved that after what happened in the anime.
It's also interesting that I didn't get to know any of the girls all that much. Even Kotonoha was mostly a pure ojou who finally fell in love with a guy, but that might've been because I was constantly humoring her while avoiding Sekai like the plague. In spite of that, it took them right until the end to actually open up to each other and for Makoto to give up on Sekai once and for all.
Also, replaying the game and setting the speed multiplier to anything but normal speed makes characters go ridiculous GLaDOS-chipmunk mode, which I find hilarious. I'll probably stop railroading as much my second time around and see if things feel any less unnatural that way.