I would say either to sell her as is and let the buyer decide if they want to rehair her, or fully customize her and sell the custom, or if you find something you want to do (alt rehair, etc) to keep her in your collection, that's ok, too =)
It kind of comes down as to whether you are determined to sell, and whether a custom or a chopped Nirvana would fetch a higher price. Up to you, I don't really know.