While I agree with you that AOA is paramount, I'm not sure I catch your drift regarding wing shape. Its generally taught that a very small amount of ice build-up on the leading edge can reduce lift by 30% and increase drag similarly, due to the change in shape. Light frost is to be taken seriously as well as it causes early separation. Admittedly, I have only read bits of this thread so I may be off base with what you're getting at.
VG's aren't part of the curriculum, but I will go so far as to say that the purpose of VG's, as I understand it, are to 'delay' separation. I need to look into this further.