That can work. Or even a static scale at the low and high end, with the slider calculating a score in the background. That way you're not distracting the rate

That can work. Or even a static scale at the low and high end, with the slider calculating a score in the background. That way you're not distracting the rater with changing numbers. Or even more simply, why not just have a Thumbs Up and Thumbs Down icons (with "no selection" being a neutral score) instead of a slider? You either like a design or you don't- do you really care about how much you like or dislike something (unless you're tracking exact scores in the background for some kind of a ranking system)?