Wisdom makes you pretty. That I like. Obey the king and don't question him. Laws, yes, autocrats, no. If you keep the commandments, nothing bad will happen to you. And if you believe that, I have some swamp land in Florida I'd like to sell you.
Everything you do will be judged eventually, and that's what makes us so miserable: we don't know when our day of judgement will be and we can't stop it. So moody!
Because there are no immediate consequences for being evil, people keep doing it, up to 100 times more. That seems like an easy thing to rectify.
Injustice: yes, sometimes bad things happen to good people, and good things happen to bad people. All the author can do is assure us that those seeming indiscrepancies are meaningless and the solution is to eat drink and be merry. Okay, I'm starting to see his game here: use drugs and sex to distract people from the misery of their lives and inequality of their living situations. Too bad it usually works.
Finally we are reminded that men will never understand what god hath wrought. At least until science is invented.