Elves are either shown as good or bad. I kind of liked the dark elves in Thor. It made them shown in a different light from what I was used to most of my life.
The Dark Elves in Thor were interesting, but I felt they could have been made far more nuanced and less one-dimensional than they ended up being. It would have been far darker of a movie (no pun intended) if we'd had learned that Malekith's forces were merely a doomsday cult that didn't represent their entire species, then leave it purposefully ambiguous whether or not the Asgardians knew that when they wiped them out.
Seriously, it'd be fitting to make the Asgardians the villains at some point because their portrayal in the MCU repeatedly shows them as extremely smug, egomaniacal and rather authoritarian in how they use their advance tech to dominate the other realms.
Actually, now I think about it, the Asgardians sound a lot like the Evanuris...