There's some question over ideal spring rates, but according to
RT's calc, the stock rear spring is 20% too stiff for your weight. With the rear too stiff, it'll tend to skip instead of properly absorbing bumps. The fork springs are a bit soft for your weight too, which will only make the rocking horse effect more severe.
I wouldn't expect these differences to have a huge effect on how the bike operates, but I am a big proponent of getting spring rates to match your weight. You can try to set your sag to see how far off the springs are (if they're too far off, you won't be able to get proper free and static sag settings at the same time). Any decent aftermarket shock should come with a spring matched to your weight (whether that's lighter or heavier than stock). Some of the GSXR shocks have softer springs too, if you'd rather DIY and save some money.
https://www.ninjette.org/forums/show...02#post1023302 The SV650 shock actually has about the right spring rate.