Spec V After market/bolt ons

Okay, so I know the spec doesn't really offer a wide range of after market options for shaving off track times, but what are all of the options that are worth the money and effort?

I know about:

Flywheel
Underdrive Pulley
CIA
Header (best gain, right?)
Exhaust (barely worth it, mostly for sound from what i've read)
Short shifter
Cams
Balance Shaft

Besides forced induction or high dollar mods (didn't include light weight rims on the list $$) what other Mods did I leave out? Also, what mods would be the most affordable that would really make a difference in the handling of the vehicle? Do sway bars really make that much of a difference? I'm just trying to see if we can make a list and determine which mods are the most effective and which ones to do 1st. I know the header should be the 1st step, but I just ordered a Nismo R-Tune CIA. Is that decent? Maybe there are some new things that have come out recently that some of us aren't aware of that we can share. No ECU chip yet, eh?

nearly every bolt on is going to net you big power gains. the qr25 is a motor that responds very well to just basic bolt ons. the exhaust will help throttle response even if it doesnt give a huge gain in hp. but headers, CAI, balance shaft eliminator, cams, pulleys, flywheel all will give good gains. one of the best things you can do, however, is get sticky rubber on light rims.

if your going to do racing besides drag, id invest in some stainless brake lines and high quality street/track brake pads. you dont need to upgrade the rotors or calipers unless your going to turn it into a serious track whore.