Since you asked for feedback, I would recommend treating the facial expression and the pose as separate. Depending on art style, sometimes people do this by separating the whole head, other times by giving the body a blank face and drawing the face on a different layer. Since you already appear to draw the head separately, you would just not merge that into the body.
The benefit:
Currently each face only has one pose, so you have 6 pose/face combinations. But if you had the heads separate from the bodies, you would have 6 faces * 3 poses = 18 pose/face combinations, and your files would be smaller without the duplicate data.
So you'd set up the PSD like:
- Head
- Expression
- Eyes, Hair, Etc.
- Expression
- Poses
- Outfits
- Base body
EDIT: Itch decided to post this before I was done, rip