I don't have much time to read lately but MKnR is an exception.
Even though there are things that might feel forced or be against one's preferences...
For me this series is a jackpot.
Before I got influenced by Japanese culture my favorite book by far was Count Monte Cristo. And after I got into anime and manga, my favorite characters were the anti-hero types as Lelouch, Kira, Alucard and so on.
The settings and description of battles make me shiver when I imagine this series being adapted as anime by some decent studio. Magic circles, beautiful visual effects, rivers of blood and that all centered around characters that show that the author was writing about something that he was passionately working on.
Some might not like it but for me, the fact that it was originally published as web novel is one of the positive points. It shows that it was written as the author wanted to...
Without taking note on how to present it or thinking that something might be seen as controversial.
I'm not delusional enough to think that it would leave any noticeable impact on society or literature. And I don't know how about how it is in other countries but the things that are criticized in the book are something that I see here in Czech Republic all the time.
I won't go into deep details but I think that it is the same in many countries: The educational system is set so the children/pupils/students learn to parrot some information, which they probably won't ever need (apart from writing/reading and basic calculations). I could see this quite well when I was on grammar school, there were 3 kinds of people in my class 1st group was intelligent people, 2nd group was those who can study and the last one was those who got accepted only so there would be enough kids in class... In a learning environment where real intelligence and ability to connect concepts has no effect on the test scores...
This was one of the points I could really relate to.
Anyway... my point is that one could find faults, and I don't think that author fully utilized the potential he had, but at the same time I can't find any solid reason why I wouldn't recommend this series to anyone...