This is really good, maybe it's a bit early to say something like this, but with ch1 alone it reminds me more of normal jap VN than the typical porn plot fuckfest AVN you see. Honestly, if it was already completed and it kept the level of quality that CH1 had, I'd be willing to buy it.
The plot is pretty good. The subject matter itself (volleyball) doesn't appeal to me, but it seems the focus is a lot more on the characters and creating a compelling narrative surrounding the subject matter rather than the sport itself, and it does a good job at it. I was very much invested.
The characters take the spotlight here, they are definitely interesting and likeable, the one I liked the most was definitely Lexi, but I still want to see more of the others. They follow some typical tropes (delinquent rebel, the wild dangerous girl, rich ojousama type and such), but I don't see a problem with that, I'm more interested in how the Dev will develop them, tropes are tropes for a reason, they work.
Gameplay is typical VN gameplay, you have choices you pick on certain occasions and seems like it will have a hidden point based/flag based system, I haven't tried every option, but It didn't feel like anything was forced on me, I don't know if the dev will keep up multiple routes based on choices (it can be a bother to code) but for now it's satisfying.
The character models are good, I don't think they are the absolute best I've seen for HS2, but this game is definitely up there in terms of quality, the girls are very attractive. We are told multiple times the MC is handsome and it actually feels justified here, he also looks good. I do like when the MC is attractive as well if I'm forced to stare at his face for several hours (no i'm not gay).
Criticisms have already been made by a few other reviewers and I've noticed these flaws as well, lighting on the scenes is quite weird and everything looks really bright, quality of the renders is definitely lacking, but this could definitely improve over time. I'm also hoping the quality of the animations and sex scenes improves, but I believe there is only one for now, so there isn't much to judge.
Overall, very promising, but I will keep my expectations reasonable, I've seen other promising games here eventually getting abandoned on going into development hell for years, so we'll have to see if the Dev's update schedule and ETA's are reasonable. If they are, this a very good start for him and I do hope this blows up and gets more attention, it's already better than a lot of stuff here.