[brusk]

Not to be an ass but the first mod I would do would be the driver. Unless you have a skilled racing background I would take some driving classes, racing and driver safety. And that's not an insult I feel that everybody should take those. That is alot of car for somebody without the proper experience of starting with lesser cars. Unfortunately the last decade didn't produce any nice fun RWD cars that the 70s, 80s and 90's did that most enthusiasts grew up with. My driving around in a RWD car most people got to learn how to drive a car to it's limits and understand the balance of cars and how they react at on cars that didn't have the limits of these cars. You might consider getting a set of wheels and really cheap tires, a JB4 that you can turn off the boost and gradually set it to higher power levels and find some back roads or a track and learn the car. From there keep upping the power on the crap tires and when you can handle all that in all weather situations then swap you tires back knowing the chances of you not being able to handle the car are alot slimmer.

Other than that a tune, intake, intercooler, DP's are the typical path for more power and M3 suspension, bushings upgrades are the path to a nicer feeling and handling. If you got E85 you can run a mix and take advantage of that for more power.