I really liked the Manga.
None of the characters felt over the top or annoying, the story wasn't all over the place and connected nicely. This would have been an 8 or maybe even 9. But then the half-assed ending came, and it went straight down.
I hate cowardly endings like that. If the story is still going, okay, I can live with the MC being unsure, or have feelings for all girls/boys. But they should always make a choice at the end.
So I ended on a 7/10 just because of that shitty ending and cowardly choice of the author.