Welcome, and having tracked a 2010 3.8 Track a bunch of times, I'll throw down some advice:
You want to do handling/braking first, that's a great start - I assume you'll figure out your tire choice as per your preferences.
The first weak point is going to be the pads - I don't know how hard you can drive, but EBC Yellow or anything more aggressive work great on the track. I did Hawk Semi-Metallic for a while and they were amazing.
The stock rotors are good and I've stuck with Stoptech slotted as replacements. If you don't plan to ever drive in the wet, Stoptech or Brembo blanks are more than adequate.
The moment you're on good pads, you're going to notice brake fade.... probably within the first 3-4 hot laps on a warm day. If you want better longevity out of your brakes, some good high temp brake fluid is a MUST. SS lines are OK but not neccessary, but they do stiffen up the pedal and make harder stops a little easier to feel the limit of grip.
Not much more on brakes you need to worry about ... a few minor upgrades and they're good (at least for me) for consistent 20+ HARD laps.
On the handling front, you'll see in the 2008-2012 suspension section some mentions of how lowering the car is counter productive to the steering control arms / front suspension geometry. Keep that in mind and either look into buying aftermarket that has better geometry and behavriour at lower ride heights, or compensate with an aggressive front alignment (as I have made do with)
For coils/dampers - Bilstein's adjustable dampers are worth the cash if you are serious about dialing in the behaviour of your suspension. PartsShopMax are popular and 1-way adjustable - I have these and find only the 3/4 to stiffest damping settings are usable... great for track, rough on the road.
There are lots of folks running 9.5F 10.5R - look for something with a 22-25 offset and you're good to go, just make sure they're confirmed to clear Brembo calipers.
Sway bars will reduce your body roll but if set too tight in front they will induce more understeer than stock. Keeping your rear too tight will also make the front end push while simultaneously making the rear act like a boat anchor. As always, adjustable is better than static - I went with Stillen adjustable and went with a mid-point stiffness in front, and softest in rear. I also picked up PowerGrid adjustable swaybar endlinks to mate up with my newer coils and dialed up the preload so there's no swaybar slop.
For alignment, to each their own, but if you're dropping on stock front end steering components, I've seen recommended dialing in extra camber in the front... I run -2.6 up front with 0.0 toe and a full 8 degrees caster. The steering feel is heavier than stock but turn in is instantaneous compared to stock sloppiness and the extra camber lets the stiffer suspension on the heavy nose dig in without leaning the tire over on sharper corners. This comes at the cost of inner-tire wear longevity, but my rears go well before my fronts so I don't really mind. In the rear I've tried a smidge of positive toe with mostly straight up & down 1.0 degree camber and eventually settled on 0.0 toe in the rear as well. Some drivers want the oversteer on throttle, I like it a little more neutral but tail happy when I really demand it.
Dropping weight in the front is huge for neutralizing understeer - lighter battery, lighter exhaust, lighter headers (if you're running track-only) all help incrementally. A nice aftermarket rad will help keep coolant temps down - especially useful if you're going to run distilled water instead of coolant. If you run really hard in hot climates, aftermarket oil cooler helps a lot too.
Getting out of handling now - some stuff that didn't make me faster but made me enjoy the car more:
Buttoning everything down: Engine mounts, shifter bushings, transmission mount and differential mounts will help with the high RPM shifting, prevent gear lockout, and just feels so nice.
Track Day Diagnostics - I run Torque with a preconfigured set of audible/voice alerts if my coolant, cat, etc. ANYTHING happens to go to crap, and I leave my audio on phone bluetooth and crank it so I can hear it. I've had one hot day where the coolant creeped up higher than I wanted and got the warning through the radio before anything happened... feels like a spaceship and can save you some heartache
Lots of people here who have done far more than me (eg. the steering components/arms stuff) that can chime in, take a look in the suspension section on any topic and you'll find lots of folks testing stuff and sharing their experiences. Good luck on the build, take your time and research and always keep in mind the characteristics of how you want the car to drive and build to that, not to someone else's opinion on how it should handle.