Rainbow's element of harmony is the only one that doesn't have flames around it, and i wanted to do wings with the armor, that's why i made flaming wings!(It seems like a name of something you eat...) The color of the flaming wings in fact is the same of Rainbow's coat. But for the effect that makes you're right, i wanted it to look cool or badass. For the armor... If i must be completely sincere, i drew armors a lot before watching Gurren Lagann. The flames? You got the insipiration right, but the armor is all made by me.