I understand where g.williker is coming from because when we start tinkering we *will inevitably face an instance where you went too far or approached incorrectly because our "can do" is greater than our understanding of operation at first.
I do think there are a few places aside from angles on sears and hammers that can be smoothed up conservatively. And there are also spring replacements however you have to use your judgement when it comes to altering forces required for operation.
Stamped trigger bars with uneven surfaces, firing pin blocks, pivoting surfaces or other metal-on-metal contact surfaces can be stoned/polished. But you need to look hard at the design and ask yourself "is *this* point of contact really responsible for the rubbing/grittiness?" - and ask if it's worth rubbing off the finish (if not stainless). I usually avoid sears, hammer angles, and externally visible surfaces, and leave that to use/dry firing. Squirting an abrasive compound and cycling the trigger action is not something I would do, as a real smith has a few decisions to make for a proper trigger job regarding a new angle and degree of engagement - which would produce more desirable results than wearing down the existing one.
However on your CZ75b, I would look to Cajun Gunworks at their DA aftermarket options, they seem to be able to do a lot. You could install the parts yourself or send it in.
Here's what I wish I knew when I first started tinkering.
A "smooth" trigger pull and "light" pull weight may have surprising effects on each other. Sometimes lighter doesn't always feel smoother.
Results are usually very subtle, you'd really have to know the trigger to tell. Many chase after a certain expectation and keep going on that part until ruin - rather than saying, "yes, no burrs, it's slick, it's the best I can do here". Avoid using a dremel if you can. Polishing/filing/stoning to the point where you change dimensions/introduce slop will have a detrimental effect. Shooting and cycling the trigger will accomplish much the same except for specific parts for a given design.
Alter the cheapest replaceable part first. Start with your least valuable firearm. The sideplate on a special revolver of mine reminds me of that every time I see it.