[horatio]

I disagree. Nero being devoured by his desire for revenge is indeed not the focus of the movie but it is not something tangential either. Like in the previous copy of TWOK the motivation of the villain was fairly unintelligible.
Either you write your villain decently or you truly make him a minor character. You cannot have it both ways, deeply weave (Nero isn't a mystic entity like the whale probe who just enters the story at one point) him into the story and then excuse abysmal writing via turning around 180° and pretending that he is totally irrelevant.