Let me put it another way. If the model holds the reflector you will obtain a different picture than if she/he doesn't. Not necessarily better, just different.
The main problem with this portrait is that the sitter has dead eyes, there's no catch lights in them, it could have been improved by asking the model or an assistant to hold a white or silver reflector in front of her in her lap out of shot to bounce some light up under her chin and into her eyes to put some light them. The picture has been shot wide open and it looks to me like the point of the sharpest focus is the tip of her nose and fall off progressively after that, not where it should be her eyes , it would have been better if shot with a stop or so smaller so the whole face was sharp.
The main problem with this portrait is that the sitter has dead eyes, there's no catch lights in them, it could have been improved by asking the model or an assistant to hold a white or silver reflector in front of her in her lap out of shot to bounce some light up under her chin and into her eyes to put some light them. The picture has been shot wide open and it looks to me like the point of the sharpest focus is the tip of her nose and fall off progressively after that, not where it should be her eyes , it would have been better if shot with a stop or so smaller so the whole face was sharp.
It is your prerogative to accept or reject any criticism of course, but if you want to learn something about portraiture it may be a good idea to consider the advice given, and don't expect everyone to say how wonderful your portraits are without offering some constructive criticism like they do on Flickr because they don't know any better.