Beth,
I think your flesh colors are very believable in a plein air palette.
I also wanted to clarify the term "graying down the background." I prefer the term "neutralize." I think it is advisable to knock back an overpowering color with its compliment. In the case of the purple background, I would use orange or yellow to tone it down.
One last note. In this painting as well as in others you have posted, I see a tendency towards candid, photographic poses. I don't care for candid portrait as a rule, I am very committed to portrait conventions.
One of those conventions is that even if you are using photography, you place your subject in a pose they could hold for 40 hours if they had to. You also take control of the photographic process. You don't just "catch" the subject in a pose, you watch the subject, and then heighten the characteristic gestures that you note. You place the folds, shift the elbow, etc., making a more pleasing composition without disturbing the underlying gesture that is the subject.
I will put a telephone book under the seat of executive to raise their tushes up to create a lap, making a more pleasing seated composition....have them sit on the tail of their coat, tuck in their shirt. On the
Fancy Lady portrait, I had Lyn practice the very beautiful limpid hand gestures and stretch out her body for the graceful pose.
By controlling the moment that you are painting, the lighting, the clothing, the body placement, you can control the rhythm, the message, the dance.
Let me put it this way, If you snap a photograph and paint it, it is like a composer recording street noise and going home and transcribing it exactly to paper. Cars honking, sirens, a kid with a boom box ... cacophony.
If, however, you go outside and listen to the street noise, make notes, observe it, and then go back home and rework it and move things around, stretch things out, tuck in a fold, look for the rhythms, you might create something magnificent, like George Gershwin's "An American In Paris."
Peggy