For me, it’s NAMOR.
One of the biggest sells for me is actually based on the overly popular INJUSTICE version of the DC Universe. In their attempt to make Aquaman a bad ass worthy of standing up to evil Supes they eerrr …. well they essentially made him one of the more famous portrayals of Namor. He was condescending, arrogant prick who just happened to be bad ass enough to pull it off. That has been Namor for roughly 80% of his existence. Imitation is the grandest form of flattery and the normal “comics imitate each other” jargon aside, I find it telling that for this to work they made Aquaman into Namor.
Now, I think the overall depiction of the characters makes the choice easy as well. The entirety of the premise of comics not withstanding, Namor has never been or even really looked silly as Aquaman has. There’s no “so he talks to fish” bits about Namor. The birth of the Marvel Universe with the Silver Age really gave Namor an outlet to be asserted as a prime player. When you’re one of the first to tangle with the flagship characters and get a prominent antagonist role early on with the book that launched the age … yeah rubbing up against the Fantastic Four and being billed as a baddie worthy of that? Stage is set pretty well I’d say. Though, that’s just icing on the cake. Namor was a bad ass before that. This dude was one of THE three major characters for Timely along with Captain-Freaking-America and the original Human Torch. The King of Atlantis was running the streets before the streets were even a thing. In fact, he was a top billing act at the absolute beginning of the super hero era.
There’s more. The modern fascination with the “anti-hero” fits Namor to a T. I mean, he was the first one. The writers at Timely, and then Marvel, used Namor as a vehicle to reflect the rebellious, anti-establishment movement of society that formed and crowned during the decade before and first decade of Marvel’s arrival to comics. It was a perfect match given who he was, what he represented, and how he was always of the “having been disrespected” mindset. Aquaman never saw such play as a vehicle or outlet for real time social awareness. Not anything like being the embodiment of it as Namor was anyway. No, Aquaman was running back up duty in anthologies and was depicted as essentially a water based vagrant with a wrecked boat for a home. DC themselves only drove the perception that the character was a throw away with his depiction on the Super Friends cartoon. They all but pointed their own fingers and laughed at his weak powers and overall MEH-ness. Sure, he’s has shining moments over his tenure but he doesn’t have the track record of being anything close to what Namor has been since day one.
That’s my take on it … got one yourself? Let me hear it. Don’t agree? Change my mind …