I mean in terms of his power not his character.
King being a unique race; Queen being a cyborg and connected to Germa will be important but I don’t think it should’ve been reasoning for “king > Kata” or “King is on par with Marco” and that stuff
King being relative to Kata and Marco come from the general mechanics of the story. If the emperors are relative to one another then why should we believe their commanders aren’t? In fact I believe Oda knows this himself and that’s why when discussing Shanks’ crew he makes sure to specifically mention his commanders as being different.
See Oda wouldn’t have to go out of his way to specify that Shanks’ men are unique IF the story AUTOMATICALLY just assumes that all the commanders vary wildly. Like if this were true, then Oda saying Shanks’ men are unique is redundant because it wouldn’t matter since ALL the commanders should be considered unique so pointing out Shanks’ men is a waste of time.
the mechanics of the story just immediately tell us this stuff and Oda knows this. He makes sure that all the commanders have unique powers and stuff but all the yonko also have unique powers yet they are portrayed as relative to one another so once again, Katakuri’s future sight and Marco’s Phoenix fruit and King’s mystery race are all unique things to them but portrayal wise, they are all about the same strength until Oda makes sure to separate them somehow like he did Shanks’ men.
And yes I’m counting King’s mystery race as part of his strength because that’s the only thing that matters about him, his strength. By this I mean his primary role in the story is to fight someone so it follows the biggest plot detail about him is fighting related. Like he’s not going to be like Pudding where her race ability is completely non combat related yet his main role is combat.
And also, the man is on fire. Like surely this is some hidden fire power that he can use. The man’s called “Wildfire”... And how would Oda explain this guy just being on fire all the time if it isn’t Technology (which Queen already covers that) or it’s some weird race thing. And we’ve seen Fishmen have race related abilities with water so a race with fire abilities works as well