You're going in with the right mindset, then. I'd seriously consider doing an autocross or two (there's one on the 9th, register today if you want to get in!) with your car as it is. That will help you understand what the shortcomings of the car are, and you'll be able to tell a little better if your mods are "helping" or "hurting" you.

Without that baseline "testing", you could go out with your new suspension, feel great steering response and think that all is well... never realizing that the car understeers as much or more than it did when stock. In a nutshell, you need to calibrate your "butt dyno". The more experience you can gain, the easier it will be for you to dial in your setup. (it still won't be easy... but there are plenty of folks like me who are happy to point you in the right direction)

Good place to continue this discussion would be for you to tell us not just what parts are going on the car, but specifics about those parts (spring rates?) and how you intend to set the car up once they're installed.