New springs can tighten up the car, but will usually result in a slightly higher ride height, even if they say they lower the car. I used to have Racing Beat springs, and the car was higher up than when I started, so I was kind of disappointed with this. Also, after a few months, I wasn't very happy with their performance either.
So, I replaced those with coilovers. This allowed me to choose a stiffer spring rate, and also to ride height exactly where I wanted it.
Another thing that made a very big difference in the "leaning" of the car was swaybars. Again, I started out with a Racing Beat front swaybar, but later moved up to the Respeed tubular swaybar which I like much more. It is much lighter and stiffer than the RB version.
What you have to decide now is what you want the car to do. Are you interested in all in racing? SCCA Autcross is a lot of fun (check out my videos), cheap at 20 bucks, and a great way to learn how to handle your car in extreme (but very safe) conditions.
