Concerto Note is a game I bought years ago and stuck in a small box containing my 'rainy day classics' without playing it. Recommended to me over eight years ago as a classic kamige, I essentially forgot about it until I saw that Cross Concerto was coming out soon.
This game uses a 'parallel story' system with a flowchart, where obtaining items on the non-true paths is required to complete the true path successfully. This particular type of system is fairly rare, but it occasionally pops up in 'true heroine/path' games.
I'm going to be straightforward on the heroines... the heroines don't really stand out as being unusual, except for Rito. Wakana is your standard optimistic genkikko, Shirayuki is your standard frail ojousama, Seika is your standard 'is liked by girls more than men' type (fights, talks and acts like a man by Japanese standards, etc), and Sayori is your standard gentle-mannered oneesan type (with maid as an extra element).
Rito, on the other hand, doesn't quite fit into any of the standard archetypes. On the surface, her interactions with Shinya make them seem like standard-issue 'husband/wife childhood friends' who practically finish one another's sentences, but their relationship is much more peculiar than it seems on the surface. Moreover, Rito is an excessively rational person who can figure out just about any situation from the smallest number of clues. I say 'excessively rational' because, as is noted in the story, she mostly separates her emotional state completely from her actual course of action, and she doesn't make knee-jerk reactions to others (except Seika and Shinya). She also possesses eidetic memory.
The story in this game focuses on the protagonist and friends (which people become friends varies based on whether you are on Route 1 or Route 2 of the common route, with Route 1 having Wakana, Shirayuki and Rito's paths; and Route 2 containing Sayori's and Seika's paths) as they try to combat the unnatural bad luck (or rather lack of fortune as Tama puts it) that is befalling them. This is mostly done by stealing other people's luck through Tama (directly in Shinya's case, and in a contagion-style manner with the others) to counter the fatal misfortune waiting ten days in the future from the beginning of the story.
To be blunt, the weakest point of Concerto Note's story is the really short period of time in which the story occurs. Forming a strong romantic relationship between the characters feels very unnatural in Seika's and Shirayuki's cases due to the time constraints and lack of previous connection.
Wakana's path (which is the one you are supposed to play first) suffers from Wakana being one of the game's two weakest heroines along with Shirayuki. Where this path stumbles is in the central conflict... or rather its source. While it is the sort of conflict that would be believable in a charage (where details are generally vague in any case), in a plotge with as many precisely-used plot devices as this one, it felt forced.
Shirayuki's path also suffers due to the heroine's weakness... but it also suffers because Shirayuki's connection to the protagonist and friends is so weak. In a VN that covered a longer span of time, the events in the path would have been more believable, but the kind of actions both Shirayuki and Shinya take in this path came very close to breaking the suspension of disbelief at times. Emotionally, the path is more touching than Wakana's, and the central conflict is much more believable. However, the romantic aspects were forced/hurried.
Seika has a similar problem to Shirayuki but to a lesser extent. The extreme nature of the situation where Seika gets involved with the group in Route 2 of the common route and the common elements to both her and Shinya's personalities and backgrounds made her path less problematic to believe. This path also manages to have a more believable conflict than Wakana's (which is the least believable conflict in the game) while matching Shirayuki's path for emotional impact.
Sayori's path is my favorite other than Rito's. While Sayori is a secondary character in most of the paths, a strong effort is made to fill out her character in this path... and it succeeds. Moreover, the romance in this path is cute and believable, and the emotional connections feel the most real of the paths so far.
Rito's path... is extremely heavy, both story-wise and atmosphere-wise. It tackles the darkness behind Kannagi that is only hinted at in the other paths, as well as revealing just how Shinya and Rito became friends (specifically rather than in general terms). It also tackles the truth of Tama and the reason why the characters suffered from such extreme misfortune. Compared to the often comedic nature of the other paths, this path is often grim or sad... but it also feels like a culmination of all the scraps found in the others.
In other words, it is a standard true path, with perhaps a steeper gap in atmosphere than is the norm. However, this was familiar to me from other Applique games, as many of them have similar shifts in atmosphere between paths.
It is easy to understand why this game became a classic. While it lacks the sheer impact that Tasogare no Sinsemilla had, the relationship between Rito and Shinya quickly became one of my favorite parts of the story. For anyone who wants a good plotge and isn't an art bigot (as in, absolutely hates anything made more than five years ago), this is a good choice.