I'm gonna start writing Rosalyn later this week hopefully, so... we'll see how she comes out exactly haha. Hopefully unique and fun!
Sarah's last scene is one of my favorites so hopefully she'll please~
Minor choices do have a fair number of callbacks, but they're not always obvious ingame cuz there's no popup. Celica has a *lot* of line swaps in her Wind training especially, based on your relationship progress with her, some of your choices throughout it, etc. Sam will remember if you confronted her outside the house or not. Ashley's stuff with Metatron gives you a few extra lines if you spoke with Maya or Metatron enough to learn much about their martial arts.
It's not perfect and not always telegraphed, but they're fun and I try to keep up with them when it's relevant!
Doing a lot of time-related stuff isn't likely though, it's harder to track.