My top 10
I don't believe king's blood is a misinterpretation, but there is definitely power in magical blood. That is shown with Jojen, which makes things easy to comprehend, as Jojen isn't royal, but his blood is necessary, but removing the power of kingship would be wrong, because if we consider it, Varys is not magical, but he was pursued for his blood and the CotF are magical, but their blood wasn't the one needed for Bran's third eye.
I think there is something to it, but I can't quite put my finger on it
furthermore... could 'king's blood' be a misinterpretation by mel and other's in her religion and really the "magic" in the blood isn't through kingship but through the magical properties?