I've noticed that are a few ways to modify the trigger pull of a rifle, although they vary in cost and complexity. For my purposes, I would most likely be looking at modifying the trigger on a CZ rimfire rifle.
The cheapest way to do it is with spring kits from folks like YoDave, MCarbo or Gunbloke. You could also replace the entire trigger mechanism with something like a Timney trigger unit if one exists for your model. Finally, you could get a gunsmith to work on the trigger.
Are there pros and cons to each method beyond cost?