The lack of common isekai tropes is really refreshing to read. Even the tropes that are there aren't too garish. The mc is a bit op, but he's not stupid. And its nice that the world building means the the characters are conscious of overuse of magic, which in turn means they don't treat the mc like a saint for introducing basic technology.
I'll also add that the earlier comments are downplaying how bad his sister and her friends are, and the mc's uneasiness around others because of them makes him feel more human.