In general, I am not interested (or only marginally so) in technical perfection of images (sharpness, resolution, exposure control etc).
My aim is always for visual or emotional impact.
Sure, I am always interested to learn more about technical aspects (and I take on board any useful suggestion), but it is not what makes me tick.
Ideally, an image will be visually/emotionally impactful AND technically "correct".
But if I have to choose one, then it is the impact and not the technicality.
So that dictates also what I look for in C&C.
If the emotional content is an aspect of photography that does not really interest a particular viewer, then I don't expect any comments from him/her.
And conversely, if technical data-crunching is what interests a particular viewer most in images, then I am afraid that this viewer's opinion does not really matter to me.