The principle that ignorance of the law is no excuse is seen as a limit on ordinary people. This was not unreasonable back in the days of common law. The nanny state has made it into a joke. What if we reframed it as a limit on government?
The legislature would need to produce a brief and clear set of laws. The executive would need to give some lawbreakers a warning on their first offense. Judges could throw out cases based on incomprehensible laws. And good citizens could actually be expected to know the rules of the game.
I'm not sure it relates directly, but I want to toss this in: Reserve violent punishment for violent offenses. Let the punishment fit the crime.