as far as shading goes you are pretty well good on it

Tough one thing that might help achieve more visual depth would be to remember that thick shaggy fur can cast shadows upon itself. one layer of fur atop may cast a slight shadow on a visible layer beneath. and I would probably use darker pools of shading where the jaw overlays the neck. they kinda blend in with one another because they are so close tone wise. Lighting effects on fur is a bit different. because most times fur itself is not what you would call shiny say for certain types of fur. but to attain a look of say areas of light and dar, highlights and low lights, that usually comes from playing around with shading some more and varied shades of grey.

With pencil I find its easier to attain good lighting effects with layers of applied pencil. Start out with the lightest shade for the area you want to appear lighter and graduate to a softer lead and just add more layers of graphite to areas you want darker. say for instance around the eye. I would darken beneath the brow of the eye. for one it would bring out the eye a bit more and giving it a less flat feel.

really when working with shades of grey in any medium it just comes around to playing lights and darks. areas that stand out the most will be where your lightest shade meets your darkest shade. its a principle that is easy and interesting to play around with. I am hoping this makes sense....lol and am hoping this helps in the least bit

overall thought. a very beautifully done piece with stunning attention to detail!
I applaud you!

Thank you very very much and thanks a loit for taking the time to reply to this in such detail. I will take it to heart and correct it as soon as possible ^^