These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Designated Villain: The Ogre seems to be this at first, for despite his bad manners, he wasn't evil, and even allowed the Buffoon to stay overnight at his mansion. However it is later revealed that he had indeed done bad things, robbing people of their money.
Fridge Logic: While the ending is written to keep children happy, adults may conclude that The Prince did not really learn from his experiences and may not be fit to be a ruler.
The Prince did seem to learn from his mistakes; whether his final speech indicates that he had not is a matter of opinion.