Having completed all routes of The Fruit of Grisaia, I'm not quite sure I would strongly recommend reading this one to most people. And even if I would, definitely not as a starting point for VN's in this genre.
Grisaia's a pretty basic set of romance stories, with a twist that every one of the main characters, protagonist included, carries some kind of difficult past and/or mental scars. Thus, every route is your run-of-the-mill school love comedy eventually leading to protagonist and his chosen one to confront the issues, and a single choice that either makes or breaks their lives. In nutshell, this pattern is my main issue with Grisaia. I didn't really expect a masterpiece-level writing, but would it hurt to add some variation? Maybe more endings (surprisingly, there is no "neutral" end), or at least more choices. Making Makina and Yumiko's route not so similar would have been nice too.
That said, Grisaia is not really bad. If you wanna get that romance itch scratched and maybe add a tearjerker or two, then Grisaia would do nicely enough. Hell, if you REALLY resonate with any of the girls, then you might even really like this one. I was mostly interested in Michiru and Sachi by the end of common route and ended up liking their routes the most. So "read for a bit, see if you like anyone, read their routes then bow out" seems like a good enough strategy to take with this one.