MC knows too much and too little. I guess author is trying hard to make him not be too op, but also be too op. He does not know HP universe, but author makes MC act like he does sometimes. But my main issue is the LOTM system is hard magic system and introducing it to HP universe without explanation that makes sense just feels plain wrong, ruins the mood and does not really fit the soft magic system of HP universe.

Author wrote some random words and called it a story. MC in Minato era, and all facts before are mostly just wrong. The story starts when MC has been in this world for a long time - author casually just skipping the actual story part on how MC navigated this new world and just had him become the 'big brother' of the important characters. Also when MC talks about his reform, only BS come out of his mouth. Smooth brain trying to write a deep story but using childish views. Think of MC's words for more than once and it all falls apart.