I too, highly resonate with the whole indigo kid phenomenon, same with being an old soul (I am 21). Ever since I was little, I always felt alienated and different from my peers. One good thing about the label indigo is that it gives a certain sense of importance to being different and recognizes that uniqueness. The only problem I see that comes with any of that kind of differential categorization is the ego and pride aspect that may arise.
However, above all else I feel the most important lesson and message to spread is the amazing power of LOVE.