I've always read that the stiffest end of the car slide first.
In your case the rear slides first, meaning the rear is stiffer in relation than the front.
Softer rear springs, smaller rear sway bar or softer tires (less pressure) would help.
On to the other end of the car.
Stiffer front springs, bigger front sway bar or harder tires (more pressure) would achieve the same result.
I think shocks provide a comfort or performance ride, not contributing much to the front and rear balance. Just my thoughts.
If you're looking for a more "sport ride" (with the stiffer sway bars I figure this is your preference) maybe stiffer front springs would suit your tastes.
Springs are generally listed by spring rate (lbs/ in.). I think the load rating is more related to ride height.
Scot at GNS Performance has personal experience with auto X road racing type stuff and as well as other venders carries UMI Performance products, a very reasonably priced parts supplier.
For reference, the searches I've done suggests the stock GN spring rates are 420 lbs/ in. front and 120 lbs/ in. rear.
The informative posts from Scot and others convinced me to get the UMI 1" lowering springs (same height as worn out stock springs) which are rated 600 lbs/ in. front and 130lbs lbs/ in. rear.
I have the springs installed, but with other upgrades and life going on, I haven't had it on the road yet so I cannot comment on the ride.
Best of luck getting things sorted out.