Don't waste your money on a ton of crap...well, actually it's not crap, it's just expensive stuff you don't really need.
Don't worry about cryo'ing rotors or cross drilling or slotting or any of that. Just use a really good pad with good calipers and good fluid and lines.
You've done virtually everything right so far. The only thing I'd recommend is that you try the Carbotech Pads. I use XP11s up front and 10s in the back. You can run these on the street too. These are racing pads that are unreal, so you may consider going a bit less agressive...possibly the 10/9 combo or maybe even 9/8 combo. All these will work great.
Go to Rockauto.com and buy lots of cheap rotors and keep them on hand...and run them til they crack. Once they crack though, trash them and put on new stuff. Any time you slot or drill or dimple rotors, you take away brake surface area. The reason for slotting, etc. long ago was to release gas buildup between the pad and rotor. Today's pads are so good, you don't need that. It looks cool, but will just wear your pads faster and won't stop you any faster. I've experimented with a bunch of combos over the years and I just run the stock stuff now.
I use the Motul 600 fluid and it's awesome. I also use the Goodridge lines.
The last part to check is/are the calipers. I'd recommend you replace them once a year. You can get them for about $105 each. The problem is that they spread over time and cause some brake wear abnormalities. Running in T1, I replace the front twice a year and the rears once a year. When the top of the pads start to wear more than the rest, it's time to replace the caliper.
Do all that and save your extra money for more DE events. Keep learning the car and learning to drive and put the extra $$$ in the bank for more tires and brakes. If you decide to go into racing into a catagory like GT1 or something like that, then modify the hell out of your car. Until then, enjoy it as stock and drive the piss out of it!!!!
The bottom line to all of this though is the old saying: "Speed cost money, how fast do you want to go?"