There's a pacing problem that makes this a bit boring. At the very least, I wish the MC was a bit more interesting to compensate for that. But no, he's like an npc, a super boring npc. Anyway, this is written well, but it is a on the boring side. And sometimes, MC acts stupid.
This is a classic example of author trying to reach his word count quota for the day. Every scene is rehashed and reused. New enemy can't be beaten, hide to strengthen, villain appears, acts innocent and then whoops his enemy's ass after a long nonsensical chats, then people praises him, then leaves the place. Scene loops.
Self-insert MCs joining strawhat pirates at the earliest part of the story is gonna be bad. At the very least, make his powers unique as well to make it slightly interesting. Terrible.