I have a couple of questions around this.
Firstly, what happens to the performance when I have a sizeable resultset of set-valued data?
I've seen similar ideas implemented in the past that look fine for the Movies and Actors or Books and Authors examples but fall apart badly when you query a number of fields (20+) that have sets within them, which can happen on say, a sizeable reference database of marketing information.
Another question: How deep in the graph can I go, and how much circular reference protection is there? E.g. if I query Movie.actors.movies.actors?
I'm interested in graph databases and data modeling and while it offers some convenience I'm always skeptical but hopeful (mostly from having lost a lot of hours) that these problems have been solved sufficiently to keep performance good in practical use cases.