Here's a quick redline for you!
To explain a few things in detail--
(Though I won't detail everything since you can always just compare and contrast with my redline and the original lines)
Your drawing already has some very good bones, and you have nice linework. You already have a nice shape going on for the head, and you have the shoulders on your canine defined nicely.
My main suggestion would be to work on how your orient your subject. I believe that you had a normal standing pose in mine, but the way your legs bend have him pulling a bit far backwards. I'd recommend straightening the legs out for a strict standing pose-- you can flip your drawing to get a better handle on where your drawing is leaning.
Also, don't be afraid of making legs and paws shapely. Some rounded curves and defined ankles can do wonders.
Another big suggestion I would make is to not be afraid of making the neck thicker. It's tempting to make necks slim and thin, but with large dogs and wolves-- especially those of the fluffy variety-- they tend to have a sizable neck, both in actual mass and fur. Thickening the neck can give a much more solid look to your canine.
Some other small suggestions I would make are to draw the eye facing forward more than to the side (and smaller), to put the tail a bit higher-- and make the mass of the tail near the rump thinner (I love how you drew the tail actually, but it would suit an otter more than a canine).
I have some tutorials compiled here that might also be of use.
Hope some of this helped! C: