Road, or track? Track is easier and more one-dimensional. Road is trickier. Stiffer springs may or may not help with that issue, as what you very well may be looking for is compliance. It's all a compromise, if you watch David Donner's run up Pikes Peak (under a thread called "New 991 film" in this forum), you'll see the compromise he chose to avoid losing big time on the smoother lower sectors. I've been road testing cars on mountain roads like that for years, and what matters most is not perfection in one condition or the other—because you won't get perfection in both—but predictability, which feeds driver confidence.

Would be interesting to see what Tom and/or Mike at TPC might have to say there, as you're already using DSC.

 

The DSC GT file already commands the shocks to their max output during higher loads. If the excess body roll wasn't there before and its here now it could be that a shock(s) is worn out losing its damping output, or a broken sway bar link.
If everything checks out fine and you want more roll stiffness then add stiffer sway bars. Stiffer spring help, but stiffer sway bars are more effective in specifically targeting body roll.

 

Spot on. Its all about having versatility of the intended usage.