IPD Sway Bars
My car has a fully sorted suspension system, and I found that the sway bars were overall the biggest improvement to handling that I made. I actually installed the stock sport bars first (my wagon had NO rear swaybar from the factory), but the IPD kit was still a major improvement over them. I am surprised to hear you say that the tail of your car comes around easily – that’s unusual in a fwd car, and a larger rear swaybar is intended to reduce understeer by stiffening up the spring rate on the rear-end. If that’s the problem you are trying to correct, there is likely something else going on.