 Using the same coloured mount and same tone as the background of the portrait isn't a good idea, there is no contrast.
Framing
 See the difference when you don't add a mount, there is hardly any contrast between the background and frame.
| |  Here I used a pinkish coloured mount which relates to her skin tones and is lighter than the background giving contrast. Here both the frame and mount have been added. The frame is roughly the same colour as the background, hair and scarf which harmonises well. Also the frame contrasts in tone against the mount.
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