you can never out-perform the weakest link in the system.
look at chungs pic. strong model, make up, hair, lighting, concept and photographer.
your model, while probably an extremely nice person, is never going to give you the strong stuff. modeling is an appearance based performance business. its tough to say to someone that they are not true model material.
our job as photographers is to objectively evaluate our subjects. in some cases, we can't do much and while we can capture them, we can't make them look like something they are not.