I'm getting very pissy over the Dark World hate. I put it in my top 5 MCU films. I enjoyed Ragnarok but the whole "Hey, I didn't like the other two Thor's and I bet you didn't either" attitude got tiresome fast.
My favorite Odin is Dark World Odin. My favorite Loki is Dark World Loki. Dark World gave Frigga a part. "Mu mu!" is one of the best lines in all of the MCU.
It had a terrible and boring villain. Which given it was Eccleston is a damn shame. But then the only actual character interaction he really has is with Frigga in one scene and that works pretty well. (The other scenes he shares with Heroes are pretty much rants.)
Oh and it has one of the only musical scores that I listen to start to finish. (OK, all three of the Thor films had great scores.)