What if all those times we were asked to join the forces of evil, we could say yes? Or what if at the beginning of the game the test would tell us if we should be light or dark? Kingsisle would already have most of the existing worlds that it needed since light and dark always tend to overlap. If a person chose or was assigned the dark side, they would be sent to a different school with different spells and even learn how to cheat. Instead of trying to save the spiral they would try and destroy it with help from people such as Morganthe. Kingsisle could always create a separate game for the dark side too, that could still involve a lot of the worlds we have encountered. What side would you choose?
That would be a huge amount of work, they've already got their hands full with Wizard101 and Pirate101. Us pirates have yet to receive a story update in 3 years.