Ares should pander to violence and rage not because "hahaha Amazon, fall before my evil evilness of pure evil!", but because he sees it as a testing ground for those worthy to exist. He sees it as nature and survival of the fittest manifesting itself in man's nature, believing that peace causes stagnation, not advancement. Peace causes laziness, and through such unpreparedness for war time, civilizations make themselves weak and susceptible to conquest. He also questions how much of his acceptance/adherence to violence is his logical analysis of its results, or how much is his own nature.
Wouldn't this give him an interesting angle, and elevate him beyond potential being written as a generic Doom lord?