To be honest with you... there really isn't anything else you need to do! Your system is GREAT!! as it is and throwing extra money into it by setting up RAID's won't give you the boost in performance enought to justify the additional cost.
If you want to do something else because you have the "itch" or cash... I recommend looking to build a lower end AM3 or i7 750 build to fill your upgrade needs. Sell the PC and continue the cycle!