Man, I love Aquamanto the point where I was basically the go-to guy back in the Comics Alliance days when they needed someone to defend Aquamanbut I dont think I could go as far as to say hes the literal best. Like, I wouldnt put Aquaman on a list above Superman or Wonder Woman. But I do think he is vastly underrated as a character.
Setting aside the fact that the reason most people think he is dumb is due to a misunderstanding of his powerswhich creates a feedback loop in which creators then try too hard to make his powers NOT look dumb, which only makes the book actually, measurably dumberArthur Curry is a really interesting character that plays a role that other characters dont.
Arthur Curry is a man of two worlds in a way that even other _____ of two worlds characters arent. Superman is an Earthling and a Kryptonian, but it is incredibly unlikely that in his adulthood, hes going to be called back to be king of Krypton. He inhabits a liminal space in that he belongs to two incredibly different cultures, while standing apart from each of them. He was raised among humans, but his powers make him an outcast. He is the hereditary ruler of Atlantis, but his own people reject him for his human background. He protects the land from the sea, and the sea from the land. He tries to use Atlantean tech and magic to benefit land humans, and he tries to modernize Atlantean society with human political science. Both reject him. Hes perpetually stuck in the middle, yet never ceases to fight for both sides. (This, btw, is what separates him from Namor, who only cares about Atlantis.)
Aquaman as a book has the potential to be the Game of Thrones of the DC Universe, since Aquaman is basically Ned Stark. Hes the last bulwark between the monsters of the depths and civilization. He doesnt usually get played that way.
He is also, of course, King Arthur, though that doesnt get played up enough either. You sometimes get that connection, like in the Waterbearer era, but that was by attaching him to the Lady of the Lake and such, which is not the obvious connection. You have the rightful heir of a great kingdom who is raised in isolation from his own kingdom only to inherit it as an adult. He then assembles a team of like-minded heroes to help leverage might in service of right. This is text, this isnt me saying, Oh, heres what I would do. Thats
thats what Aquaman is. But you dont get the parallels to King Arthur as explicitly as you should, imo.
Also hes friends with an octopus, and that rules.