A nice article! It really does a great job of describing the hostage nature of keeping the various daimyo in check.
One thing that I think is commonly misstated though, is that this period was one of "peace".
When viewed from the elite perspective, the power struggles between daimyo in the Warring States Era had subsided, but for the common people, the Edo Period was anything but peaceful.
The samurai class could chop up any commoner at any time, for any reason, or no reason. Sometimes just to "test" a new sword, or because their "honor" had been challenged (maybe the person didn't get out of the way and bow fast enough).
> The samurai class could chop up any commoner at any time, for any reason, or no reason.
This is a pop history misconception. It was always a rare criminal act, and to the extent it did happen, it was specifically more common in the Sengoku era. Article 71 of the Tokugawa Shogunate's 1742 penal code explicitly specifies public execution as the designated penalty for this crime.