One issue I'm having with my newest idea for a free game is the element of 'plot twist'. Developing a game freely available to all means that I have to let many people know about any plot twist I put in the game.
Another way of putting it is this; if I make a game that is known for a complex plot, or has complex twists, then people might try and read what these were first (if only to see whether it might be worth playing). I have to make the story publicly available for game designers, coders and so forth: how can I easily hide it for others?