I pitched this idea a long time ago in the IRC, but I figure I may as well post it here, since it might be something we may want to use.
The Elements of Dissonance are the opposite of the elements of harmony; instead of the seven elements of the finer points in maintaining a pure life and conscience, they are the seven deadly sins, which are...
Lust
Gluttony
Greed
Sloth
Wrath
Envy
Pride
The idea is, that these elements of dissonance aren't restricted to one pony and/or some other life form representing the entirety of that element, but in fact, multiple ponies hold them, whatever they may carry the most of in their hearts, as if a curse set upon the world's population by an intangible evil. These elements would cause dissonance in these ponies, spiraling society and basic rights downhill to nothing, until each pony is tearing at one another due to insanity, or alone, suffering under crushing depression.
To escape the element of dissonance, you must overcome that vice. You may be given a new dissonant element, but it's up to you to overcome that, and be a better person-- er, pony, and save others from that same fate.
Juuust throwing it out there, now that I've thought about it a lot more.
