I don’t have any experience with the P-09, but in a SP-01 Shadow or Shadow 2 it’s pretty common among USPSA shooters to install an 11.5 lb main spring to lower the DA pull weight but many of us also replace the stock firing pin and FP spring with an extended FP and reduced weight FP spring. This combo ignites CCI primers reliably, and no need to go to Federal primers unless you opt for the 8.5 lb main spring.
A TRS and floating trigger pin also makes sense to replace as the TRS have a tendency to break over time.
All of these parts are available from CGW.
Again, this is for a SP-01 or Shadow 2, but I run a 10 lb recoil spring with minor PF ammo.