In terms of how I enjoyed each route,
Nayuki > Shiori > Mai > Ayu >>>> Makoto

It felt kind of bad to ignore/shun Nayuki on the other routes. She's so there and always nice and wanting to spend time with us.
Nayuki's route felt the most natural. She's very endearing. But also the interactions and progression were good. Sad we didn't get any Nayuki in a ballgown.
Shiori's was the most romantic I think Probably because she pushed the idea of dates so early on but it made sense given her haste. I also liked getting to know more about Kaori through this route and their family dynamic.
Makoto was ... well, I found her annoying in the other routes and that didn't quite change in her own route. I was able to find her cuter but as she lost her ability to speak the route became rather redundant til the very end.
I actually quite enjoyed all the interactions we had with Mai and Sayuri on her route. The part where we tell her it all in her head and she's done this to herself confused me and I'm not quite sure I understand but overall I loved the character interactions in this route which definitely boosted this route just above Ayu's for me.
Ayu's route did help me like her more overall but I still don't quite see her as fitting in the romance area. The sex scene especially was like... unsure if Ayu even wanted that or understood what sex is. Which is also how I felt about Makoto's. The part where Akiko gets sick and Ayu does all that work and her feelings are shown so clearly to me are probably my favourite parts of this route. Also was a bit surprised to find out that Ayu was not dead but in a coma. I liked her hat and hairdo in this

Overall I really liked Kanon. and it made me eat Strawberry Jam Toast for the first time probably in over a decade