I can tell you really like doing the face--because that's easy to make out. But, when you go down the right arm to the hand that's really close to the viewport--that's where it's hard to make out what's happening. I thought the paintbrush was actually a leg for a while, because that's where a leg would typically be.
What I would do is take some photo reference, because it's really hard to hold a brush like that, and I think that's partly why my brain is having a hard time processing it.
Also, right now the shoulder is pointing down towards the ground, which, because it is a pivot point for the whole arm, would not cause foreshortening, even in the hand. If the viewport is looking down at the dog, he should be painting above him, I believe, in order to cause that foreshortening. I think if you went back and rotated that shoulder, it would help my brain register that the hand is what's in front of it.
It's also hard to make out the hand, when the middle and pinky finger don't appear to be part of it since they are the only body part with that much shadow. I actually at first thought the middle finger was the chair, and I read the outside of that finger as the silhouette of his abdomen.
Overall though, I like that you're going for such a difficult pose. It's a really cool idea.