This manga has had it all for me, up until nearing the end of the story.
It was perfect. I was excited and wanted to know more, wanted there to be more of what I'd grown to thus far like.
It was even good after the "major change" in the story, but that was only for a short while.
In the last few chapters my connection with the story dropped.
I was attached, but then that what I was attached to disappeared.
I just think that this manga, this story has had something perfect up until a point, but then had unsuccesfuly taken a turn, aiming for an effect that with me was a failure which almost ruined it all.
For me the effect was negative.
It decided to break its course from the well-established one that I'd grown to love.
It bugs me because I, now that I think of it, feel as if the story that I fell in love never got finished and that I was left with a single option which is to read another story with the same characters and that serves as the continuation to the story that I love(the remainder of the chapters).

I think it could've been done much better, albeit that would probably also mean very differently..
It's not like my displeasure is caused because "omg my favoruite ship didn't set sail", it's that I think that the last arc is poorly done.
I mean, I have enjoyed the story so much until that certain point. Then when the event occured, my connection to the story grew even more, but that only lasted for a short while because I had begun realising that.. How do I say it..
The story simply started kinda heading for another focus, a focus which was not what it had had built up within me up until that point as the focal point of the story.

The following 1 sentence is spoiler-ish:
10/10 untill the "river dip" and shortly thereafter.
6.5/10 from there-on.

The characters are all loveable, and how loveable they all are and what they had is what I grew to love, the story connecting them.
This manga has it's thing, but it turned out that I myself have misunderstood the manga and that it is actually something slightly different from what I had grown to see it as before the end-game chapters. :/

Regarding the side-stories, which don't have a dedicated listing on MAL but are accounted for in the listing of the main manga(the ERASED manga has 44 chapter, and it has 49 chapters here on MAL because of the 5 chapters from the side stories volume being accounted for in it) they continue on in the perfection which to me was this manga before the final arc, so the side stories are a 10/10.

EDIT:
I guess I've missed the intended focal point of the story..
"A city where only I am missing".
Still, I think that the ending arc is shabby, so I will bump the overall score from 8 only to a 9.
I stick to what I've said, this manga has something perfect, up 'till the part where it turns out I missed the intended meaning..
Would've been all 10s had it stuck to what I thought it is, or, had the final arc been done somehow "better"..
It's a great story overall, now that I've changed how I view the story, but the end arc is somehow not on par with what everything before it is.