No need to be safe, I don't know a lot about Aquaman comics, but I guess he isn't usually depicted as a half-moron biker-bro. But Snyder's vision of Aquaman was just boring, besides a few cool poses / shots. Maybe it's his problem, not enough "cool" comics panels to trace his scenes over.
Wan isn't playing safe, he already showed us an Aquaman pushing a submarine out, swimming full speed, glimpses of underwater cities, some "lord of the rings" feels with the different clans, big war scenes with giant crabs against neon stingrays and mesosaurs, rooftop pursuits with a guy shooting energy beams from his cool helmet...
This guy uses his imagination, and is not trying the "what if this guy existed in our sad and dark world" angle. And I believe he will make the Aquabro fun and sympathetic, and make the transition to an Aquaman usable for future movies.