For me, it'd be RAINBOW. I think the original melodies and production leave a lot of room for experimentation and reinterpretation, and considering her current vocal style, I think a fresh take wouldn't be overly subpar in comparison to the source material. Would love to hear a trancey or housey reproduction of Over or Dolls and maybe a bossa nova take on Close to you.
For as much as A Song for XX has dated production, I wouldn't want it re-recorded; I think she's at a different point in her life now and the emotion wouldn't come out in her vocals in the way it would need to in order to make the lyrics shine like the first time. Though, I think an unplugged reproduction of the record with remastering on her original vocals would be tempting. Or, even a more dated sound that would make the record sound a little more city pop, which I think would fit the original vocals quite nicely.
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