Well, it doesn't seem to me you are considering the differences of European monarchies when you are judging people.
Frederik will never have a work schedule like Felipe and Charles,
he will be king of a small and politically stable country with a mainly ceremonial monarchy.
But I am quite sure he is prepared for his limited role and he will be a popular king.
And as for Spain and Britain, yes they are more important and more difficult areas,
but their monarchies are mainly ceremonial too and the role of their monarchs is limited too.
King Juan Carlos' role was more important because he had to restore the monarchy in Spain,
but it won't be the same for his heir.
Therefore I stick to my original comment:
The importance of the European royals and especially cps is over-estimated.
(although some of them do make faces as if the future of their countries depends on them)