-Y2K actually did happen, but was stopped by some time-traveling kids, a frog, a robot, and a cavewoman. -In the future, the military will develop the technology to develop anything they need out of mysterious blue crystals. -Disney characters are real, and exist on very small planets. -The power to shoot webs is only useful for rescuing construction workers and balloons. -All gay men are skilled in the art of war. -Everyone in the seventies consisted of, at most, 3 pixels.
I think it would also be cool if Nintendo took the time-traveling concept from Link to the Past to its extreme - have Link travel to futuristic Hyrule, to prehistoric worlds, etc.