You cant just "bump the fuel up a bit"
The engine uses a MAF sensor, to measure the volume of air flowing into the engine, and bases the fuelling on these values.
If you up the fuel pressure or fit larger injectors alone, the ECU would notice the engines running rich, and trim all the extra fuel out by cutting back the injector opening time, resulting in either you being back exactly where you started, or with it popping a fault code because its reached the limits of its adjustment.
If you want more power, you need more airflow. If you want more airflow, the ECU needs to be mapped for it, because if it sees too much airflow then it will simply drop into limp mode expecting an fault has occurred.
The only way to fool it, is to fit a larger MAF housing. This in effect scales the airflow map by the % area increase of the new housing over the old one, and so long as its accompanied with matching injectors, will fuel more or less correctly and make more power.
As an example, switching from the stock 2.5" to a 3" MAF housing, is a 38% increase, so long as you couple the housing up with 38% larger fuel injectors, you'll end up with more or less 38% more power. It can make the engine a little prone to boost spikes though, so it may be worth installing a MBC in parallel with the N75 to act as an upper limit on the boost pressure.
The other issue is that if your ecu is already mapped, you'll be requesting 38% more power than the already mapped car, and you may well find a k03-073 cannot supply that much airflow.