Here it is after camera raw adjustments in Lightroom. After some small adjustments, I increased the contrast, blacks & vibrance, and used a gradient to darken the skyline somewhat.
Next, I plan on tweaking the details, possibly removing the leash and some of the odd fur patterns on the dog's back.
I worked on the back fur with the clone tool
The patch tool worked great to remove the part of the leash that was hanging down.
The context-aware fill got rid of the dog tags and the dog's junk (although this is not something he's too happy about). There was also a tiny bare branch next to the dog's nose I found distracting - gone like magic.
I used a brush to desaturate in the dog tag area as well as the dog's belly, since I wanted his body to be white.
I also found that using smart sharpen in a fur area after using the clone brush gave it back the realistic texture
The rest of the leash is proving to be a big challenge, and I wonder if I should just round out the end and give up. Getting back the edge of the leg, as well as the part of the back paw that's covered are the two big challenges. Thinking ahead in the field would have worked wonders. :/