It seems too obvious to be worth saying: the law should be simple enough to understand that people of good will can comply with it without engaging a lawyer.

Very few of us have a lawyer in our back-pocket nowadays. Sure, laws regulating some kinds of financial transactions and contracts are necessarily going to be complicated and hard to understand. But the general rule should be "If the law isn't something an ordinary person could be expected to know, then they aren't bound by it". That would put an end to clever-clever legal drafting.