Hotchkis bars are somewhat unique since they are tubular and relatively light. KWs have progressive springs. I've found that they tend to roll quite a bit. But body roll isn't necessarily a bad thing. You don't want the car so stiff it becomes twitchy.
I think your first step is to make sure you have fresh bushings in the car. Then choose a good damper/spring combo. Swift springs are supposed to be the new rage. Maybe Bilstein sports with swift springs? I think you'll need new front perches and rear spring mounts.
2013 F30 328i - Melbourne Red
2011 E90 M3 - Monte Carlo Blue
2004 E46 M3 - Imola red