Or alternatively I'd just make Aquaman the best hero in the DC line up. One thing, I wouldn't make an empathetic link to marine life his main ability because sorry to say it's cheesy. I wouldn't remove it but I wouldn't be dedicating panels to it. What I would do is make his main ability his ability to manipulate water and other liquids. With the backstory that his royal blood makes his water manipulating orders more powerful and nuanced than Mera. I'd have it be that while Mera can manipulate water to varying degrees, Arthur can manipulate almost any liquid. He can harden it to the tensile strength of steel, compress it on a quantum scale (stole this from Invisible Woman) making it sharper than any known metal, he can create water from the very molecules in the air we breath. And under the right circumstances and duress he can manipulate the liquids within solid objects. Similar to Bobby Drake he can even move around by manipulating the aforementioned air molecules. This is on top of his super strength and durability for obvious reasons.
Naturally he can command the sea as well. Those skills aside, because he's a nice person he holds back ala Superman (and Mera is like Supergirl in which zero fucks are given usually). But unlike Superman, AM will drop you if he feels he's been too nice to you. No need for random hand attachments and shit.
He now has a primary power that has multiple uses offensively, defensively and on support. And he's no longer a fish out of water when fighting on land with no ocean near by.