Optimal Fun: Game Complexity vs Number of Players

One factor seeming to have a strong influence on how well I enjoy a particular gaming experience is how well the number of players matches up against the complexity of the particular game. For the same game, too many players or too few can drastically alter the "fun" generated by the session. Certain games seem to scale rather well, having a wide range wherein playing is quite enjoyable. Others have smaller range while many have a very narrow sweet spot. Complexity can take the form of rules density, amount of decision making required, number of bits to manage, or even sheer length.

Thinking about this today, I sketched out the graph above. The ideal, optimum fun game experience is represented by the blue line. Above the line is chaos and frustration. Below the line is boredom and stagnation. The curve for each person sitting around a table definitely varies depending on factors such as individual preference (i.e., for group games, for instance), maturity, knowledge of rules, mood, downtime tolerance, complexity tolerance, and commitment to making the game work.

My thought is that games fitting most closely on the blue line when played will tend to be enjoyed more and hence played more often. Perhaps the 4-player Twilight Imperium 3 would be more enjoyable and less chaotic? Adding additional complexity and players to Shadows Over Camelot seems to have improved the game's fun factor...

Anyway, back to doing my taxes.... thoughts?