One of the common methods used to explain or teach a roleplaying game to someone is to liken it to a movie. It begins by asking the new gamer to remember her favourite movie and then to ask her to imagine herself as the protagonist of that story, making decisions as that character would decide. Unfortunately, this is a flawed model of story-making for all gaming groups. That kind of story has one or two protagonists, along with a cast of dozens of interested parties and even more people who might never know the story but who depend on the protagonists.
The gaming group is more like the kind of movie that has an ensemble cast. There are more than one or two main characters and as the audience of the story we are meant to be interested in all of them. So, as a game master, it is important to understand the differences between the popular story-form that has only one or two protagonists and the story-form that has many characters. For the former, the story is about those characters. It is about their struggle and their triumph (or failure). Those kinds of stories are best suited to games with only one or two players.
Conversely, the larger gaming group is the ensemble cast. The story is rarely about those characters but is more often about a theme that connects them. Take the movie Higher Learning as an example. This is a movie with an ensemble cast, with several smaller stories that interweave and ultimately meet in a tragic end. However, the movie is not about the story of any one of them. Rather, it is a story about racism and acceptance. The key to the story is the theme and not the narrative of the individuals.
So what kinds of themes are present in our games? What is the theme of the adventuring party in the fantasy setting? Perhaps it is nothing more than adventure itself. How about the cyberpunk setting? Rebellion against the domination of corporations and government. So, as GMs, we need to ensure that our stories are about putting those characters in to those themes and situations, and about giving opportunities to explore those themes. Without paying attention to these themes we are left only with the many variations on the level-me-up games.