Side view: back is too arched, body isn't long enough. Ears are too long, eyes aren't black and beady. Tail is too short and too fat.
Facing us: ears shouldn't be pointy, leg placement looks like he's stretching ( front legs should be less visible).
Contrast on body could be increased a bit. Be sure to use photos of real rats as photos, knowing rat owners there should be no shortage of good references online.