What do you want out of your car?
perhaps a tune would be nicely suited with your current mods.
If you are in sydney, you can get a remap done for little as $400.
Why not get a r34 cooler, or fmic? thats about 500.. thats 1k gone..
With the other 1k, do more suspension mods? Castor rods, tie rod ends, sway bars etc..
But the next step in more power will be costly!!
That is if you wanna go bigger turbo etc. You will need a budget of 5k for that.
Perhaps with the 2k, invest it into insurance