i decided to go ahead and finish this, just because i like to practice. fixing the dress shading/coloring was a little more tricky than i had anticipated. i ended up doing the brightness/contrast, but also did some airbrushing and cloning.
i made a new blank layer for the rest of the skin and did it the same as i had done the face, except i could do it all on one layer this time.
on the background, i selected the darker areas and then airbrushed that. killing the selection, i then went around and touched up a bit by hand and followed that by airbrushing the whole and putting that layer on a soft light blend mode.
i also went around and touched up minor areas with push and airbrush.