After Effects for shadow or brilliant light?

[Gary Douglas]

I'm shooting something at the moment. And I have a scene where, I have a completely white material covering the back wall. Now I want that back wall to be completely brilliantly lit, but yet I also want shadows without the subject looking like the lighting has had a harsh effect.

 

So basically, if theres no pracitcal way of having soft skin tone with the background being seperately lit and not getting rid of the shadows, which would be the easiest and most successful looking in post? Would it be better to blast the wall with the light I need and add realistic looking shadows later on that follow the subject as he or she moves, or would be easier to keep the shadows and make the whole the back wall look like it has light shining on it on post?