Thor does classical hero stories because that fits him. They don't fit Diana. Her character is supposed to be about progress, not copying the past. If she does a classical style story, it should be in order to subvert that kind of story.
Wonder Woman's powers shouldn't come from the gods, nor should the Greek Gods be in any kind of position of dominance. The days when they were the top dogs are over, and the stories featuring them should focus on how they've adapted to the new Paradigm. Aphrodite recognizes that the time of the gods being in charge is over, so she becomes a source of wisdom and guidance for the Amazons instead. Ares, by contrast, can't adapt, and instead tries to cling to days gone by, which brings him into conflict with Diana.
Ares goes up against Darkseid? There should never be a moment of doubt in the audience that Darkseid is going to come out on top of that situation.