Fellow Javelin owner here, and from the looks of it you have just about everything you need with all the hard stuff done. If you want a car heavily focused on track use, I would pretty much copy what Asifnyc has done.
It gets tricky when you want a street/track car
My car is 100% street car, so I've had plenty of compromise on cam choice, and interior comfort and things like that.
As far as suspension and brakes, the basics are available from control freaks suspension, and Wilwood brakes.