canta per me
Yuriko Kaida's voice was so pretty for starters

, and her self-harmonization had this haunting feel with the added effects. I also like that crunchy note on the lyric "anima mia" in the chorus just prior to the violin solo is distinct. (Only replicated by Deb Lyons in her version
s).
The Japanese version almost doesn't exist in the same universe. What an underwhelming vocal performance! I am wondering if having a better vocalist would have helped or the melody doesn't seem to go as well with the Japanese lyric.

In my view (hope no one takes offense), I don't think the Japanese lyric went as well with the composition/arrangement because a lot of the impactful points of the instrumentation are not as reinforced by the vocal/lyric (in terms of how the consonants land and so on). Oh, and the Latin section during the violin solo was still included...
Deb Lyons version sounded like an American soprano using a musical theatre/contemporary style vocal to sing a song in Latin, so it was...interesting

; not bad just interesting. You could hear some of her Americanisms in her pronunciation and how she approached the song. I would have preferred a classical vocalist (with more accurate pronunciation) if Kajiura was going this route. A unique violin solo though, so cool.
Winner: Yuriko Kaida in the original.
Tsuki no Shijima
A cute song overall, Yui Makino has an baby-like Japanese voice - like a young teen Yuuka Nanri, I would suspect. Interesting. She was the voice actor so it was like a song by the character, right? I always recognize these kinds of performances since the voice actor/singer is carrying some of the emotional understanding of the character in their vocal performance. Yuriko is excellent in her supporting role with those delightful Kajiurago-isms using her breathy voice and range.
In the ultimate mix version, there was no Yuriko, which was a bummer. It was interesting to hear her nasal-like voice all over the harmonies. Her high harmony was defintely weaker and I couldn't really make out that part distinctly (of course heavy vocal effects as well). Yuriko also enunciated the Kajiurago better in the original version.
Winner: The original, of course!
Mizu no Akashi
I've had to defend Rie Tanaka's video live version a couple of times online, because people were, in an effort to praise Wakana's FJ cover, saying Rie was a lesser singer
s. so just for the record I am doing a bit of vocal analyzing due to that "bias".
Listen to the first lyrics starting from "naka ni" she's using beautiful dynamics, a bit of a plea and vibrato. She continues to enunciate the lyrics quite well. Being the voice actor also gives her more awareness of the character's journey and emotional state especially at the time of the song. That would reflect in the vocal performance as well.
I also liked the elements of the song and the gradual development: the 16th note synth melody at the background, the effect of the solo cello coming in, and the interaction with the guitar as well, including how she came back in after the violin solo (and the echo of her vocal that was added). I really felt the emotion of the song and was carried by it. Nice!
The acoustic version was the true precursor to Wakana's version, so my thoughts on the vocal from the original remain. Her expressiveness is not diminished for not having the rhythmic momentum. Strong strings and synth presence.
For the quite popular FictionJunction WAKANA version, I will agree that Wakana is a more rounded vocalist. Her tone was more open and her vibrato was more present especially at the start [of each phrase], but I still prefer Rie's dynamics at the very start.
Wakana tone, use of cry effect, and her audible breath, gives her performance its character. Stronger/louder piano on the return to the chorus before the end - a massive swell in the musical dynamics.
The ReTracks version was interesting because of the strong full string-section accompaniment that started the song. The piano took over and I really liked how the strings came back in to support the piano. OK, I think this is a strong second in musical development to the original, but I would put it over the original if I were to allow my love for classical music to take over (I'll hold it back). The ending was crazy with that compositional flourish/climax for the strings
Winner: I might just give it to the original because of the musical development (sweet), followed by ReTracks for the same reason (chamber music!), and then followed by Wakana's emotional cover for the vocal performance as a whole.