Yeah, Crescendo is also good. Characters are your standard archetypes but the writing gives them more depth than is usual. The art is really nice and some of the sex scenes are very erotic.
As a downside, since the story takes place over 5 days, there isn't much time for events to develop, but within that restriction they're well told stories and you bond with the characters quickly.
Regarding Kana Imouto, play the version with the original art. The game is unvoiced and a lot of the dialogue between the characters doesn't read well, and also some of the drama can be forced, but in spite of this it is still one of the best VNs ever because the relationships in it are believable and complex and because the story is so affecting. It's a real healer of a game, a real positive thing in the world, and it's no accident that it inspired a devoted fanbase.
You might also like (or love) The House of Fata Morgana. I thought some of it was brilliant but some was a slog and the central storytelling device made a lot of it unavoidably predictable and repetitive.