I have a 9mm Pro (4.25") and the only thing I did was putting a StormLake barrel in. Reason was a faster twist rate because 9x out of 10 I shoot 147gr.
It shoots great and the night sights are dead on from the factory. I don't see any other upgrade I want to do to this gun.
I think people have a tendency to "over engineer" things. There are soo many "fancy" upgrades available (just look at ZEV Glocks for instance) that really don't do much for accuracy and reliability. Please don't take it as lecturing the OP, it's just my observation.