This spoilerfree review is for the original game, not the anime. With the word-count limit, I'm doing better with a list than an essay-type review.
The Good:
Kareha and Mayumi. They're the two most interesting characters.
Lisianthus and Nerine. While they're very similar and hitting on the same themes, the ideas are interesting and well written.
Asa. She's the character with the most development, since she starts off much like a Childhood Friend, but unlike Kaede, it's a healthy relationship. She's a fun character who's interesting to read about.
Someone helping out in Primula's route. It's an event towards the end that may change your entire perception of one character.
The art is beautiful to look at.
The voices are performed well enough to my knowledge. I don't speak Japanese, but I am familiar with the tone they use, and I understand bits.
The Average:
Primula. I generally dislike Lolicon characters, but she's quite likeable. Most of her route focus on the plot rather than character development.
The music has its ups and downs. Nothing notable in either direction.
The game is formulaic. This means you can expect most things, but you also know what you get, for better or worse.
It's not a very long game. That means you're not going to get bored of the path you're on, but you're also likely to want more of the ones you like.
The Bad:
Kaede. She's a character who inspired a lot of pity but no sympathy for me. That she clearly needs psychological help removed most of my enjoyment for her route.
The H-scenes. These kinds of scenes aren't my favourite to begin with, but in this game they're particularly bland and clichéd, to the point where you can basically swap the name of the girl and the CGs and it wouldn't make any difference.
Kareha and Mayumi lacking routes. While playing through the game the first time, these are who I wanted a route with. They're in a new version of the game, but this review isn't about that.
The day-changing animation feels like a roadblock when you're skipping text.
The game lacks a scene replay function. There is one, but it only replays three scenes: the H-scenes and the ending.
In short, the game is good but short and formulaic. The characters resemble each other a lot, but still have their distinct temperaments. I quite enjoyed it.
Formulaic But Not Bad
This spoilerfree review is for the original game, not the anime. With the word-count limit, I'm doing better with a list than an essay-type review.
The Good:
The Average:
The Bad:
In short, the game is good but short and formulaic. The characters resemble each other a lot, but still have their distinct temperaments. I quite enjoyed it.