Considering the markings' unreality - when was the last time you seen a dog with a square on his forehead?
They're too sharp, the fur would make an irregular shape, blending more gradually with the surrounding natural color...
The paws should really be completely flat, it's that they should be flat on the bottom side and shaped on the top side... take a look
HERE, it should help a lot
And working about anatomy... Tell me about it
Still, anatomy is a thing that almost everyone can develop in - I don't think there is harder thing to master than plausible usage of anatomy
