heh, you're not going to get anywhere. You took a very evenly balanced car, loaded up the back, and went around the turn at "just shy of loss-of-grip at 70," and lifted at the apex. A little stupid, in my humble opinion. A well balanced car like the legacy wagon will brake and hold the road better than any other arangement. This of course is safer. Muck with the weight as you did, and you have to be aware of the way the car will handle. The car is designed to have predictable limits, but without traction control it can't protect you from yourself.
My suggestion is to unload that car immediately and get something with no rear sway bar or with traction control. Or, you could drive a bit more gently when you have a load of junk in the back.