If taken at face value, Baki The Grappler could considered very sub-par in terms of writing. The action scenes are amazing, the art is excellent(though very off-putting and takes time to get used to) and in general does everything it sets out to do: make a martial arts epic.
The problem that arises instantly is that after the Maximum Tournament arc the story seems to take a trip on some kind of combination of acid, LSD, and ecstasy. Up to the Maximum Tournament arc your suspension of disbelief is fully intact. Yes there are some over-the-top moments, mostly through Yujiro(crushing a man like an accordion, getting hit by blue whale tranquilizers then punching through a metal vault door.), but for the most part the characters are believable in the context of: these are people pushing the limits of their body and becoming almost
The Prisoner arc tears down your suspension and the ending of the Muhammad Ali Jr. arc is a literal Flat "What."
moment and everything after that(especially the ending) is a psychedelic trip. By the end you'll be scratching your head and either disappointed, angry, or utterly, utterly confused at what you just read.
That's if you read Baki The Grappler with a serious mindset. It would be considered average, or even below average, if taken seriously. But if viewed as a parody it suddenly becomes an incredible combination of Bo Bo Bo
and Cromartie High School poking fun at martial arts manga in general. From the main antagonist Yujiro being literally unstoppable by man, beast, or mother nature to the art style looking realistic yet cartoony; everything points to the series being a huge parody yet it takes itself completely serious and that just makes the manga even more funny. I consider Baki the manga equivalent to The Room
- it takes something so over-the-top and absurd and tries to take make it serious, making it even more funny.
And really, that doesn't make it bad, if anything it just makes it better as a series. If you read Baki with serious mindset you might have a bad time deciphering what the hell is going on, but if you kick back and read the series as a comedy manga it suddenly becomes amazing.