I can't advise anything on the trigger at all because mine is untouched. However a hammer change, in my case adding a CZ85 Competition hammer #10035 to a CZ75-C cut the trigger pull weight almost in half. Can't remember for sure now if it was called 'Competition' hammer or 'Combat' hammer, just go by the number, or whatever Dave suggests. He has kits too.
I've got a [long] lifetime of experience with complex machines assembly, repair etc. and a huge amount of 'hand tool' type experience. For me the hammer swap wasn't that bad using slave pins when I removed roll pins, to keep parts alignment, and having proper punches. Dave has the right punches too.
There were some parts of the swap that were intense, rather challenging in the 'walk & chew gum at the same time' way. Persistence is really all it took, not vast skill or knowledge. I wasn't comfortable fitting the safety to work with this hammer, but I took the leap and was blessed with a good result. There's other options besides modifying safety, you can look into that to decide which suits you best.
If you search through the stickies in various places all over this forum, you'll find some excellent pictorial guides plus all the related technical info. Also within individual forums there's many threads where guys have asked about 'how to' on this stuff. The information is here, all you need. Take a long hard look and decide whether you want to jump in, but it certainly is doable!
