they want the kind of power
One thing you and most others have failed to notice is that the legislation was not created only for when PiS remain in power.
But Duda did the right thing. As a doctor of law he found many legsilative flaws even beyond the actual merits of the case. I believe he will change the laws to give more say to parliament (less to the prosecutor general). For instance, the Sejm will proposes candidates with 3/5 support and the president will accept or reject the candidatures.