Not bad, but needs some adjustments to make it enjoyable for all players.
The pixel ratio used is too large for clean painting without bleeding into other sections of the body. This can be fixed rather easily however.
Areas such as: Hair, head, lips, eyebrows, areolas/nipples and arms/hands should all be set to different layers to prevent your colors bleeding into areas in which you do not intend.
A zoom function would be ideal in order to detail
tent the slider on the brush size and opacity bar so one can see where they are currently set
The pixel ratio the brush uses is larger than the pixel ratio of the image. This leads to issues in the cleaness of ones brush strokes.
Sorry for the long list, these changes are your choice, however it will increase game quality