After reading DC’s 528pg volume of Aquaman (including early comics), I have to say it’s not hard to see why he’s one of the less popular superheroes. Not only does he keep getting rescued by Aquaboy (the oceanic version of Robin) and later Mera (who marries him), he’s also kind of an airhead without much of a personal agenda. It’s really sad to see Mera go from a more-than-equal crime-fighting partner, who can control water and make it into bridges, scissors, ribbons, and other forms, to the wife who patiently stays at home. One comic even shows her getting depressed at this. The more sequels to Aquaman make her much more powerful and feminist.
Aquaman’s super power–the ability to telepathically communicate with sea creatures and tell them what to do–usually saves his life; it’s an interesting power because it doesn’t originate in himself (like strength, ability to fly, etc) but depends upon other sentient and differently embodied creatures in the ocean environment. Even though it turns them into something of servants and tools, it’s possibly one of the less ego-centric super powers.