I'm not sure what's the point of the movie "Call Me Chihiro" or "Chihiro-san" in Japanese. That doesn't necessarily make it a bad movie - it's not - but it does make it a strange movie - which it definite is. And much of that strangeness is due to the titular main character, Chihiro.
I've known only a handful of care-free or free-spirited people like Chihiro. And of those very few choose to live in Japanese if they can help it. The society and culture simply do not encourage or tolerate such people. So it is not at all unbelievable that someone like Chihiro can exist.
What's a bit difficult to believe, however, is that a person like Chihiro could maintain her attitude towards life and others for so long without being crushed by the pressure to conform or the very real stigmatization that happens all too often. In Japan, people get ostracized for much less.
The other major characters are also very familiar - a shy high schooler, a homeless man, a very young kid whose parents are mostly absent. Then there are the minor characters like a group of working-class guys who are Chihiro's groupies. None of them come off as being mean, broken, or hopeless.
So I suppose "Call Me Chihiro" is more like a fantasy. It is what a better society can look it, if we really want it. In that sense, this is a feel-good movie - Japanese style, of course - and as such I think it works.