One of the best parts of this manga was when it advertised it self as Yuu and Touko's story it rarely went and start diving deep into the minds and back story's of other characters especially after their parts or arc were done
Staying with the main characters in the present is something that makes it feel like the story is moving forward and characters are developing
Hellish long backstories/flashbacks of characters especially supporting cast, just steals the growth potential of the characters and plot as well
I'm glad YagaKimi was a collected story and actually managed to end well rather than start falling apart in the name of becoming a long running series
(I haven't been able to find more works by Nio-sensei, so if this was their first work, mad props to them, this is a great first)