What springs do you have in the forks? Stock? Rear? How much do you weigh?
I did the Ohlins front cartridges and Penski rear and WOW! what a difference. Ohlins rear would probably be better. Make sure you get the springs spec'd right for you for both. From the factory they are terribly unbalanced. As long as you get the spring rates sorted, along with any valving upgrades, sag set and clickers adjusted right you will be happy with it. Will feel like a new bike.
2008 ZX-10R | Black | Arrow Headers | AreaP Slip-on CF | K&N Filter |GUTS ECU Flash By Guhl Motors | Block-Off Plates | Fender Eliminator | Clear Alternatives Integrated Taillight | Rifleman's 1/5th Throttle Insert | Speedohealer | Pro-Grip 719s | Vortex Bar Ends | Puig Z DB Windscreen | CBR1000 Mirrors | Vortex 520 Sprockets -1/+1 | RK Gold 520 Chain | Galfer SS Lines | Pazzo Shorty Levers | Vortex Gas Cap | Rebuilt Damper | Lightech Rearsets | Much More To Come