Adding the spacers effectively softened your wheel rate (spring rate). That is a sign your still too stiff. You mid corner push could also be too much camber (or caster - you didn't list it). With higher spring rates (or wheel rates as you need to factor the sway bar too), you need less static camber and less caster as there is less body roll. Less body roll results in less camber loss due to body roll. Running lots of caster just adds to wheel turned camber (thus your mid corner push. If tire pressures were right to begin w/, you likely did see any gain as a result of the change. Lends to you being on the right track. you must run that 32mm bar. The 30 is just too small. That is why some folks liked to run large spring rates - to make up for some of the body roll. A push can be caused by too much or too little camber. My guess is you have too much as the push comes when you are at max wheel input through the corner. Just a guess w/out you providing where it is now.
A soft car is easier to drive. It can also be driven offline (for making a pass) easier than a stiff car. Softer rear rates will help plant to front some during turn-in, but if the F/R balance is off, it will pick up a push through the corner.
I still think 700-800F is the sweet spot. 225-275R would match. Depending on your driving style a 3:1 to a 3.5:1 F/R spring rate ratio is the target. If I had made Hallett, I would have let you drive my car to compare.

Pay more attention to tire temps across the face than wear.