Okay, so it's been a bit, and I've read up to the current chapters.
I have to say, I'm quite enjoying this. Oh, plot-wise, it's nothing particularly novel or exciting, but the story is serviceable for its purposes, and there are enough dangling threads that may or may not pan out into something plot-adjacent without drowning the reader in the faux 'rule of cool' trap bullshit that so many isekai manga authors fall into.
It's fun. Not brilliant, but fun. Character designs are decent enough, but this is elevated by really good artwork. If there's one criticism this early on, it's that everybody seems too agreeable. People who act as antagonists are immediately put in their place in standard fashion, and so there aren't any real continuing hostilities. I get it's early on, but that's a structural weakness here that I hope gets resolved soon.
There are a few 'romance-if-you-squint-and-wear-glasses' subtexts floating around, but it doesn't seem as if romance is going to be a primary theme, which isn't necessarily a bad thing - a lot of authors get lost in relationship twaddle, and it bogs down actual storyline development as all the sugary goo takes things over. And I'm getting real 'himbo' vibes from Protagonist-kun, but not in a bad way. For all that he is specifically designed to be the counter to the MC's 'Antagonist-kun' (and vice-versa), he seems remarkably, almost annoyingly affable. Serious Golden Retriever energy; a cinnamon roll made of dumb...but fun, in spite of his minimal characterization.
I guess it's still too early to call things, because we're still in the phase of finding out who everybody is, to say nothing of just who that 'everybody' is supposed to include.
I guess I'm still optimistic about the direction this is going, as I'm annoyed that there isn't more - too many unanswered questions for the 'tism in my brain to be satisfied with a conclusion.