Half the movie was pretty unnecessary. The whole sub-plot with the government worker was gratuitous and kinda just seemed like revenge fantasy. Pretty gross stuff that really didn't add anything to the plot.
The main plot with all the Daniel Craig stuff was fun, 5 stars for that. Even though it was a pretty predictable ending ("oh there are like 10 family members but here's the only 2 that we're going to give any individual screentime to... can you guess who the major players are?")
But everything else? That is, everything involving the girl with the dragon tattoo? Blegh.