For me the major problem with the character is the way he was written. Fiennes could have made him a lot more complex or tortured (in Red Dragon he managed to make a serial killer one of the most likeable characters). In the books he comes across as cold, unloving, and obsessed with power and the movies are faithful to that. Even his tragic backstory doesn't make me empathize with him more. So his portrayl of Voldemort is excellent, but I just didn't relate to his character.

Rickman's portrayl as Snape was the best thing about this movie. Frankly he became my favorite character to the point where I was more worried about what would happen to him than Harry's fate.