My personal choice is to start with the wheels/tires, then suspension and work your way up from there. There are soooo many choices out there, but Bilstein Sports is always a good choice for suspension upgrade and I like Conti Extremes for the rubber. Wheels are a personal choice and again there are a plethora of choices. A lot depends on your imagination is and how deep your pockets are. Good luck and post a pic of your new baby!
If you don't know where you are going, any road will get you there.