Never realized Yuki Kajiura was the one who created and wrote songs for Kalafina. Man, those songs are great. I can't say it will make me want to watch those shows, though.
As for LeeAndLie, well, that channel usually emphasises that the lyrics aren't anything special when you can understand them. That said, the one you linked to was particularly good. And it's really sad when their version of Lost in Thoughts All Alone was better than Nintendo's singer and Nintendo's translation.