not a flaw you dumb fucking motherfucker? Not to mention the whole hero complex thing which leads to him jumping in to help people to a nearly suicidal extent, ending in all those broken bone
His power is the most generic superpower ever. Period. The fact that he can't sustain his own power is not a flaw on the power itself. At the same way that if a 4 yo tries to fire a .454 Casull revolver single handed and hurts themselves, is not a flaw of the firearm.
That said, a story about superheroes CAN be interesting if is something new. Instead of "high school for super heroes", what if heroes was unionized and the organizations are corrupt, promotes things that creates villains and limits who can be a hero to manipulate supply and demand, is founded by publicity and tax payer money and the protagonist wanna be a hero but his super power is a taboo in that society, lets suppose that a villain in that fictional world almost destroyed the world with the power to manipulate blood and the MC now has the same power(in smaller scale since he is on the begining) and tries to conceal the nature of his power because if the origins of his power leaks, he will lose all sponsorships and will be viewed as a villain. If the MC also had more "human flaws" like for eg, having angry and resentment,
Goku? Fights the best martial artist in the world nearly to a draw after a year of training, learns his ultimate technique by seeing it once, is completely pure of heart. Yusuke does have a fun personality, and if you're an edgy teenager you may find the whole "he's a deliquent, his mom is a prostitute" thing super cool, but his powerset is pretty much the same as Deku's (super strength plus shooting stuff from his fingers for a limited number of times) with less drawbacks (no broken fingers here), and late in the show he's revealed to have super duper awesome demon blood, which instantly turns him into one of the most powerful beings in the world. Jonathan Joestar? Pretty much the ideal hero, even if his story ends in tragedy; he picks up Hamon very quickly, he gets most generic superpower(superstrength)(...)
Goku - Dragon Ball was much better before DBZ. Seriously. After DBZ, everything blows up galaxies.
Yusuke - Is not only just because he is a delinquent, is because he is funny and SMART, he shooted on the mirror to hit in a enemy from behind, used his shoes as gloves to fight a electricity based yokai and he had character growth. After his death, he realized that people around him likes him. See the video that i posted, he is not a bad protagonist. TBH Kurama and Hiei are FAR BETTER characters. And Mazokus are completely different than the christian conception of "demon" . The demon blood also influenced him. HE offered 3 humans to save his dad.
And no, he din't becomed one of the most powerful demons. Even after months of training with his father, he still lost to Yomi.
The unique problem of the series is the power creep near the end. Before sensui appeared, few humans with very circumstantial abilities managed to defeat the champions of the dark tournament. That was amazing. Luckily we got Hiatus VS Hiatus which is far more focused on abilities than on giantic flashes of light.
Jonathan Joestar, is the ideal gentleman.
And JoJo moved from Ripple towards the STANDS which are far better power system IMO.
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About magic, there are a lot of animes/mangas with AMAZING hard magic systems. Post stand JoJo and Hiatus X Hiatus are the two most notorious examples. Overlord since is extremely D&D inspired, i will not use as an example. Why with games, they rarely has decent magical systems? Magic on FF1 was OK. But nothing great