Julie,
I think the very last one, the close-up with the black hat, is my favorite. Her face has so much character. I like the shape of that hat better, it doesn't hide her face.
If it were my choice, I would either paint her in that striped chair (but without the stripes
, or I would paint a head and shoulders of her from the last photo. I think it depends on whether you want to do a 3/4 or a head and shoulders. I really like her expression on that last one though . . .
Joan