I thought the way it all came together was done really well. There was a lot of action in this movie which I feel was also done well. You weren't left thinking "Ok I've seen too much wand action now". There were some things that made me laugh that weren't supposed to. Voldemort. Although I'm not sure whether this was my immaturity or the fact that it was just a bit too silly.
For example this had me in stitches:
Overall I was impressed with this. I still think that it didn't really need to be a two parter as I don't think part one had a lot of substance.