I am not working full-time yet but as a student, but I do know that the education system in S'pore is tougher than other countries like Aust.
But education here is well recognised in many countries (i.e. China/Taiwan/Aust).
It is not true that one has to be permanently happy. Something is wrong with you if you are happy ALL of the time. Even when one is unhappy, sometimes one continues with present arrangement because the other side's grass is not greener. Unless there is threat to one's life, (as in Vietnam persecuting Vietnamese of Chinese origin after 1975 & as in Hitler persecuting the Jews in Nazi Germany) most people grin and bear it.
If you want to compare countries to live in there is always + and -.