I thought Sandman was an excellent character in all reguards. He's fully 3 dimensional. He's a villain, but you don't hate him, even when you find out he killed Ben Parker. His decisions and his grief and determination make him someone people can relate with. Who wouldn't have done the same to save their daughter? The actor pulled off his emotions with such eloquence. He was a big guy, but he wasn't just this muscular thug. The whole movie you see him as a person.
Really, I thought the CG for him was absolutey amazing. The kind of particle physics and animation used for the scene where he tries getting a grip on his new sand-form is perfect. The camera starting out at micro-level with individual sand grains and then watching whole miniature dunes moving around. The most impressive part was when he only JUST had his torso together, and stray bits of sand fell off his back a lot. It looked just like a sand-sculpure that moved. I honest to God felt like I could reach out and pat his shoulder and feel the course sand.
Plus I like how they ended it with him. A Spiderman movie villain actually living at the end is a first, and a weclome first. I'd like to see him make an appearance in a later movie and maybe resolve the plot with him and his daughter, this time appearing as an ally.
Oh, and I LOVED the fact that they fully used the properties of sand in this movie. I mean of course, how Harry's flame-thrower forged his arm into glass and shattered it. That possibility had been in the back of my mind through the whole movie, and seeing it done impressed me even more.