Sylar wanting to be special isn't stupid. It was carefully explained in season 1. His grandfather was a watchmaker, his father was a watchmaker and he too became a watchmaker. It wasn't fulfilling for him. He thought his family and his life were too plain, he wanted to stand out, do something extraordinary, be someone important, be special. Combine that with the fact that his mother was constantly telling him that he could do so much better and Sylar has a good motivation. When Chandra told him he had an ability, Sylar was thrilled and though he actually was special. That is until Chandra started to doubt that he actually had an ability.
Sylar saw these people with abilities as special and most of them didn't even want to the abilities they had. They wanted to be normal. That is why he took those abilities. Just look at that first guy he killed. It makes him a relatable character too. A lot of people want to be special, important and be rememberd for something extraordinary.
Now that sounds like a good origin for a villain but then the all of sudden the writers threw all that out of the window. Now it's "the hunger" that drives Sylar and makes him want to kill. That is just so lame and certainely not as interesting as him wanting to be special.