This review is for 0.6.4a, which was (a) my first time trying this game and (b) a complete play through. This game has a lot of potential, quite a lot of content at this stage, and I did enjoy the game, but there are significant technical issues that will need to be overcome to move foward as planned that result in me giving it a 3-star rating at this time.
The overall story, as well as the stories for each girl, is solid. However, the game is completely linear. Choices don't have any significant impact on the game except when they lead to game-over screens. It's nice to see that each girl is unique in both physical design and in their motivations, and the same goes for the guys. The writing is somewhat uneven. Mostly, the story follows logical progressions, but there are a few exceptions. Sometimes, the MC says that he needs to do something in the morning, but never does and makes no reference to that failure. The latter part of the game has a lot of English errors, and a lot of them look more like sloppiness than English-as-a-second-language errors. There's also 4th wall breaking that really doesn't add anything to the game.
The image quality is pretty good. However, many of the videos don't quite line up when they loop and some of the motion is extreme relative to the background. Some of the renders have clipping issues, for example bag straps often go through clothes. There's decent sound and music, though the more recent stuff has perhaps gone a little overboard on the sound effects.
The code is a mess. Events that happen multiple times don't call the same label, but rather are just copy-and-pasted (non-modular programming), resulting in code that is harder to maintain and change, and removing the ability to skip through repeated events. There are basically no variables, so the karma system that's in the works doesn't record karma and will probably require a fresh play-through when it gets added. Also, the game has no way to tell if you've viewed scenes, which would be required to properly add a gallery. The quest system that is shown at the end of each day (homework) is extremely clunky, doesn't accurately reflect the current progression of the story, and is completely unnecessary at this point. Some scenes where choices will affect the images shown (different states of undress for a girl) are not properly done, resulting in clothes appearing/disappearing between images. Adding meaningful choices to where to go after school is not going to be easy with the current code structure and may actually negatively impact the pacing of the story. There is at least one bug, where the game tries to jump to a label that doesn't exist because there's a typo in the day number of the label. With over 24,000 lines, fixing the code is going to be non-trivial, but really should be done before it gets worse.