Sellability: So, I think it is an absolutely lovely work of art that a lot of people will enjoy. The expression on the dogs face is fetching, and the breed you painted is very popular. Also, not revealing the face of the woman is a good idea, since it becomes easy for the viewer to imagine themselves in that place.
One thing that would make sales easier is kind of cheating–riffing on classics that everyone knows, so they can say, “hey,I recognize that, I know art!”. As an example (I am not telling you to do this) an homage to van Gogh with a vase of sunflowers on the table will spark positive associations.
Subject matter: again, I like your choice of subject matter. It has near universal charm, is whimsical, relatable, and not cheesy. It speaks to what I’d like to be doing right now, tbh.
The bottom third leaves me wanting though. It is always a balance, as you undoubtedly know, to keep things from getting cluttered. But it feels like it is missing something (perhaps even just a signature to draw your eye?)
Technique: you know your way around a brush and color. Your pallette is lovely, and your brushwork has a nice blend of portraiture and impression. Your brush work also very nicely reinforces where you want the viewers eyes to go.
The shadows are distracting from your brushwork though. Your strokes seem to imply consistent points of perspective, but the shadows don’t quite jive. Can’t put my finger on it unless I busted out the graph paper.
All in all, fantastic. And I truly hope you sell three times as many prints as you need to.
(BTW, you can tell me to stfu and I most certainly will :D)