So I know my comment isn't going to be original, but I do feel the need to add it.
This remix is the kind of thing I wish I could do: really great musical backgrounds with emotive singing.
However, the Japanese really, really ruined it for me. Yeah, I said it wasn't original, didn't I? Whoever said the pronunciation didn't bother them surprises me; it was driving me nuts the whole time; I even went to fetch headphones to make sure it wasn't my terrible speakers doing something. It wasn't. =( The translation, also, does leave something to be desired. My Japanese isn't nearly perfect, but that's the kind of thing I'd proofread with a Japanese native-speaking friend before recording.
Now, I'm not saying that my Japanese singing pronunciation is perfect or that my voice is as good as Jill's - because neither is true - but I also think that it is generally best for one to not attempt large amounts of singing in a language one does not pronounce very well. This I say also coming from a choral background. It drove me crazy when we sang Japanese songs in choir, because the pronunciation was so bad I had to laugh in order not to be annoyed out of my mind when I was supposed to be singing.
That's not all that's weird with the vocals; the timing even in the English feels... wrong. I'm not even talking about the tempo separations, I'm talking about syllables that feel poorly placed, musically.
Personally, I'd love to see this song rerecorded without the Japanese, and with a bit more attention paid to the timing. Until the Japanese came in, I was really enjoying myself listening to it, but it was so jarring that it really shattered my enjoyment. :-/
Disclaimer: I make no claims to be able to do better at anything I criticize above, and I mean my criticisms to be constructive. If anything comes across sounding mean or personal, I don't mean it that way at all and I apologize.