I think it would have to be Honesty, I'm brutally honest. I say something if I mean it, and I often offend people because of that.
But if I had my own element, it would be Hate... wait, that's not really harmonious. Then I guess it would have to be Knowledge, I'm really smart, you know.
By the way, the elements of Harmony remind me of the Satomi Power orbs from Okami.
Each one represents a different virtue, there are 8 virtues: Honor, Faith, Knowledge, Wisdom, Brotherhood, Duty, Justice and Loyalty.