Your next mod/step should be new springs and shocks. That will get rid of any softness or wander in your car. Springs account for more roll control(I feel) than sway bars do.
I assume you had a good 4-wheel alignment done when you did all the M-bits. ?
Btw... the 2011+ (all N55 cars)spring change was only the rear springs that went from progressive to a linear design.