The heavy trigger can be reduced by the owner. At the bottom rear of the grip frame is a pin. It knocks out easily (hammer should be down). Then the arched mainspring housing can be slid out.
It holds the hammer spring. You will see a small pin hole in the housing and the head of the pin on the flat side. This pin has a flat head, much like a nail. The pin captures the spring. It is one of those pins that will cause a "Sproing-tinkle-tinkle" noise as it pops an unknown part into the far reaches of your shop floor.
I clamp the housing in my vice and use a pop rivet shaft (a small finishing nail would also work) to push the pin out. Push from the serrated side of the housing. It comes out easily. Then, when I pull the rivet shaft out, releasing the spring, I cup my hand over the end of the housing to catch the spring when it pops out.
The spring has a steel piece inserted in each end. The cup end is exposed at the top. It holds the hammer tail. At the other end is a little, pointed piece of steel. Pull this piece out and then use your sidecutters to cut 3 coils off the spring. Put the pointy piece back into the cut end of the spring and then re-assemble. The cut end of the spring goes into the bottom of the housing.
Note that the housing has to be turned over so you can put the little pin back in so that the head of the pin goes flush with the flat side of the housing. I use a small screwdriver to compress the spring so that the pin can be inserted to capture the spring. The pin will go in by hand and just needs a final little tap to seat it flush.
Slide the housing back onto the frame, wiggling the hammer tail so that it sits into the spring cup. make sure the pistol hammer is down when you do this.
The trigger will now be a pound or two lighter. If you like the improvement, order a lighter spring from Wolff.
If you want it even lighter, remove the flat spring with the 3 tines in it and bend the left tine back a bit.