As part of a large project I was tasked with plotting out the Dungeons & Dragons character creation process. As the first step I plotted out the key decisions and variables between the different classes. The whole exercise was very complex and produced dozens, (if not hundreds), of graphical files. At the end of the day I rather liked the simplicity and clarity of these very initial charts.
The first chart (above) compares the eight different core classes found in the game. The blue boxes represent points where player decisions occur. Starting at the top, for example, the first decision is "race." The next decision is how tall and heavy the character will be. If you opted to play a human character, you get to decide where you will put 2 bonus attribute points. This chart takes you all the way through the racial portion of character creation.
The second chart focuses on class. (In Dungeons & Dragons the characters are comprised of two fundamental characteristics; race and class. A class might be Fighter, Ranger, Cleric, and so on.) In this chart we see that most of the player decisions are found when they get into the Skills, Features, and Powers.
This exercise was ultimately used to inform the Character Creator software.