Paper Moon
Something I appreciate greatly, about both Bogdanovich and Elaine May's films (those of which I've seen), is their refusal to moralize whilst portraying morally dubious characters and morally dubious scenarios. They take themselves seriously, whilst never lecturing.
One of the marks of great storytelling, I believe, is the ability to portray dual moods. As in, a scene being simultaneously optimistic and tragic, or both fun and cynical. The ending to Paper Moon, I believe, perfectly encapsulates just that. It is incredibly, sincerely heartwarming, whilst suggesting inevitable tragedy in store for its main characters. If any ending is deserving of being styled "beautiful", it might be this one.
This could very well be one of the greatest films of all time, and unusually for films of that calibre, I think most people would enjoy this greatly if they gave it the chance.