Ya know, I'm probably a rarity in that I really don't mind villains killing heroes. The 'good always wins' is boring from a story telling point.
What I do hate however, is scenes like in the preview, where villains kill heroes far beneath their weight class so effortlessly. It's like a neon sign by the writer to tell us that this character is dangerous, but actually manages to counter what they've shown us. Why? Because the rule is show, don't tell. And killing a meager B-lister is very telling.