Eh ... I have no idea how understand the difference "Kawaii" (or "childlike design") of Character Design between the Far East land and Western (include U.S.A.) .
For example when I was kindergarten and a primary school age, I was always terrified for Roman stone statues and plaster figures. Because it showed only the whites of eyes, no iris.
In our culture, iris means "a soul in body = alive". No iris eyes means "the dead" or "a ghastly apparition".
Maybe that is one of reason why almost Japanese Animation young character has big eyes.
One more thing, we know original "Le Petit Prince" with translated or French language book.
The Anime version is just a way of introduce Antoine de Saint-Exupéry's story.
About other responses, I will be back and translate in Japalish.
Have a break with John Lasseter's memories of Lupin the Third.