I marathoned Asatte no Houkou as part of the Great Catching Up Initiative. It is as good as everyone says, which is lucky because I only really cared for one character: Shouko. I didn't dislike Karada or Hiro, but I also didn't care too much about them, either.
Well, I didn't care for the fact that Hiro's character design mirrors the template found in just about every eroge you'll ever see. Every time Hiro was on-screen with that sheepdog hair of his, I half expected him to start boning a mosaic with his pants on.
Karada is okay, but I don't see why a 12-year-old girl should look like a four-year-old, especially when her classmate Tetsumasa is more than twice her size.
Tetsumasa was the one character I actually disliked, mostly because he was always bitching about something. Tetsumasa is the Shinn Asuka of Asatte no Houkou. I would have been more willing to accept him had there been people punching him in the mouth every episode.
I fully agree that Asatte no Houkou is a very good show—presumably doubly so if you like Karada, Tetsumasa, and Hiro more than I did. That I still found Asatte no Houkou so enjoyable despite liking only Shouko is a testament to J.C. Staff's storytelling abilities. I'm pleased the plot did not dissolve into Freaky Friday antics and misunderstandings. Rather, Asatte no Houkou focused on the trouble with preconceptions. To that end, I encourage you to approach Asatte no Houkou without preconceptions of your own—even ones that I may have germinated.