hella_sti, I'm running RCE Yellows on my wagon. Combined with Koni inserts and GTWorx camber plates/groupN rears, the ride is plenty stiff. The best thing that you can do (other than changing your springs/struts) is increase strut travel, and if possible, lighten your wheels/suspension. Per my own instructions, I am also running drex strut extenders, which help avoid the bump-stops.
Further, lightweight forged wheels/lugs, V6 STi aluminum LCAs, and lightweight summer tires all made quite a difference. I've got my wheel weights down quite a bit, under 35lbs per corner, lug nuts included. Waiting to install my Whiteline roll center / bump kit too, so I'm hoping that helps make things even better, in terms of suspension reaction time/smoothness. Either way, the search will continue for the "right" blend of firm/smooth. Maybe someday we'll have an affordable electro-mag adjustable suspension that isn't garbage.