I read the first chapter, at least. Maybe I'll read another one since there's only a couple.
Technical prose is 5/5. No issues there.
Pacing is probably a 3/5. I feel like maybe a little too much happens in the first chapter. By too much, I mean that it is both rapidly moving through content while also introducing a bunch of characters. I feel like it'd have been better off with one or the other. So, rather than what, 5 side characters? Maybe Reika + 1 for the first chapter, or maybe splitting the content of the chapter into two and introducing all five. However, pacing is a very personal thing so I'm heavily biased.
Considering you call it a light novel, I'd move that rating closer to a 4.5/5 or 5/5 as they're expected to have a brisk pace.
General content is hmm... We get a brief glimpse at the setting but nothing substantial. It is both okay, and not okay. As it is a light novel, I think it is probably pretty good. Sometimes, building momentum for the reader can be a good way to get them into the story, so it might work in your favor.
The only thing that really bothered me was the names you chose. When I get Japanese (or Asian names in general) I anticipate following the normal convention of last name/first name. You have first name/last name, which can work. The biggest, most glaring name is the protagonist's name, and I think I see why you chose what you did.
Shizukesa Hana. If read last name/first name style this looks like an extremely feminine name. Flip it to fist name/last name and you've got a fairly odd given name for the character. Shizukesa is typically a word, not a name, but that doesn't really mean it can't be. Shizukesa means something like tranquility or silence. So, it's like someone in English naming their kid Silence.
Personally, I do not like Shizukesa as the name. I know why you chose it. His name is practically a pun.
Silent/Tranquil flower. He's quiet and he probably has flower-themed powers of some sort. But I'd still go nuts having to mentally pronounce Shizukesa all the time. If it was Shizukesa Hana as last/first then I'd actually probably like it because it sounds like a good name, but the the other way around is not (for me)!
Anyway, overall: Looks like you are a talented writer and have a good thing starting with no particular flaws (except the MC name!). The premise isn't my jam, so I'd probably not be sold on it, but it'd probably do really well with the LitRPG crowd. 5/5 for LitRPG or GameFic fans who like reading light novels. 3-4/5 for others depending on their tastes.
Addendum: I read chapter two. It was better than the first in my opinion. I still don't like the MC's name.