it's great, but, like goron said, it's kinda plain...even the foreground is kinda plain. I mean it's well drawn but it just doesn't really have anything all too special about it. maybe you could try changing his facial expression and/or the lighting. i also noticed that the wrinkles on his forehead just look like lines rather than wrinkles. the wrinkles don't really look like part of the head here. the highlights should go in between the wrinkles. right now you have it shaded as if he doesn't have any wrinkles. and the nose and mouth area should have a bit more shading, like under the chin and that part in the middle under the nose and above the lips.
In short, just recently, I've created Rose and Dave to go along with a specific size / style I'm making a bunch of Homestuck sprites in, along with Dad. I made John a while ago. There's also the Sepulchritude MSPA Reader, which I don't think I've ever posted. It's basically an edit of my previous sprite, the classic MSPA reader holding a gun towards suicide, but I like it.