God damn, I really have a soft spot for the “dark fantasy” aesthetic, but I also find the character design in the genre (obviously it’s even worse in so-called “high fantasy”), with context or in isolation, usually pretty…well, boring. I don’t really know why, its more feeling than coherent argument at this point. I just never feel “Wow, this character looks really f*cking awesome.”
Even in this cinematic trailer, if it weren’t for the grotesque blood/skin-tissue cape, the “daughter of the lord of hatred” () or whatever she is supposed to be just looks like, well demon queen/king nr. 13472821 to me. And the others are all just the typical “fantasy classes”.
One prominent example, where I did experience the “damn this is awesome” feeling in terms of character design is Bloodborne and that is probably, because it throws a bit of “victorian steampunk” aesthetic (another, maybe even bigger, soft-spot of mine) into the mix, at least for a portion of the game.
Besides that, the trailer is really well directed imo. Certainly makes you interested in the game, even without knowing anything about it.
Also full disclosure: I don’t know anything about Diablo lore (only played a bit of 2 and 3), but I don’t think this should be relevant.