Most of the time, I find it's faster to redo things than to try and hack away at an existing model. In fact, it's double faster because I've learned how to do it better along the way. No model is useless, no matter if you use it or not. A good way to model is to work in 2 dimensions first. Then when you are happy with the distribution of the splines, you can start pulling the points out in the third dimension. You may even consider sketching the model first and using that as a background template. Also, remember, you only have to model half the face and flip it over. Happy modelling!!