The main flaw is director Akira Kurosawa's sentimentality. The philosophy behind the story would seem to be that all the characters are telling the truth, despite the unlikeliness of that, However, Kurosawa turns it into "everybody lies". Nice try, but it didn't fit in here. Otherwise this is really great. The only Kurosawa films I would place above it are Ikiru, Throne of Blood, and Ran.
The movie came out in 1950, so they could not put anything very bad content-wise. There is talk of a rape that happened and some mild violence. Anyone 12 and over can handle it. Though they would probably be bored.