Checking the internet, it seems that this work was extremely influential for the development of the US legal system, as well as reforms for many European systems. So here are a few follow up thoughts:
1. On Reason, Science and Education.
He proceeds with the "Enlightenment" conceit that his was the first generation to encounter "Reason", whereas all former generations had been locked into ignorance and superstition. Thankfully he lived to see the French Revolution, so hopefully he was able to repent of this view before he died. A key part of his view is that science and education would permit the taming of humanity so that rule of law would become more gentle with time.
2. On Penalties.
"SOME crimes relate to persons others to property. The first ought to be punished corporally. The great and rich should by no means have it in their power to set a price on the security of the weak and indigent ; for then riches, which, under the protection of the laws, are the reward of industry, would become the aliment of tyranny."
A swift beating would be preferable to confiscating someone's property and livelihood. This advice is turned on its head in our era where pecuniary penalties are by far the preferred mode of dealing with those who have property, making corrupt incentives the primary driver of litigation. Add to this the legal costs, and I doubt that Cesare would have much good to say about our current situation.
In general, the view is that the legal system should not be designed to encourage others to go searching and/or contriving crimes that they can then prosecute, since this will corrupt the entire society.
3. On Excessive Legislation.
There are remarks about those who would ban water so that people would not drown and fire so that people would not be burnt. He mentions gun control laws, which he characterizes as "disarming those only who are not disposed to commit the crime which the laws mean to prevent". Some arguments never quite go away. Again, we must note that his era didn't include many suicide vests or RPGs.
4. On Juries.
The juries of ones peers is mentioned here, but this is in the context of an aristocratic class and a peasant class.
Pardons are typically done by the chief executive, which he finds to be a conflict of interest. Instead, he would give the power to the legislature. Besides which, he finds that pardons are of little utility in his ideal world, since they are generally used to set aside excessive punishments.
6. On Swift Execution of Justice.
The US now has the slowest system in the history of the universe. Cesare's complaint against this is that it leaves the accused in a perpetual state of uncertainty making a punishment that is often worse than what would have been meted out by the law.
7. On Torture.
Cesare's complaints against torture are certainly relevant today. Torturing someone to to get a confession is non-sensical. Yet his more innocent world didn't have to face suicide terrorism with accomplices. How would he argue this?
8. Adultery and sodomy.
These laws he dislikes, but his argument is especially problematic. Adultery is supposedly caused by passions given to man (and woman) by nature for the survival of the species, thus, he argues that we shouldn't be criminalizing nature. Yet anger, greed and ambition are likewise passions given to man by nature for the purpose of the survival of the species, and we put bounds on these as well.
I have reached the end of this little work. What follows is a commentary by Voltaire on the same topic.