I get this, what you are doing. You have everything very soft, to draw the listener in. Very successful.
 
However, you might be making the listener work too hard, just a bit. The piano is low in the mix (I've just started dabbling with Pianoteq 5, which I like some apsects of - and perhaps you are keeping it low, so it does not reveal itself synthetic in any way? Louder pianoteqs show themselves rather faux in the upper registers particularly.
 
So you keep the piano low - and your vocal is low in level as well. I'd bring up both - the piano just a bit more, and your vocal just a bit more than that.
 
The trouble is, if you bring your vocal up, you are going to magnify the plosives you already have. Check out any lyric with a "p" ("pay the piper") - did you use a windscreen on the mic?
 
Enough criticisms - your touch on the piano is extremely deft, and your voice is beautiful in the extreme. I'm not a huge TW fan but I'd wager I'd prefer your voice on any of his songs. I hope you write some of your own?
 
cheers,
-Tom

Thanks for your observations, emeraldsoul. I'm not the artist, I'm the engineer/producer. Yes, she writes her own material and is extremely gifted at it, holds a masters in English Lit/poetry. This album was 10 years in the planning.
 
The levels are right where I want them to be and there's a method to my madness. This album will have about a dozen tracks on it, several with dense track counts. The sparse tracks like this one tend to be perceived as louder because there are fewer slices in the pie. When mastering and sequencing songs, I'd rather have to bring the sparse tracks up to the level of the dense tracks, than to lose level on the dense ones by bringing them down to the sparse tracks...made that mistake before, live and learn.
 
I don't like windscreens on vocal mics, they can rob high end detail. This is a first draft of the finished track and I will draw the explosives out with the volume envelope before final mastering, have had great success with that method. A bit of sidechain compression can help also.
 
 

Ah! Thanks for clarifying, and your responses made total sense then. It's great as a first draft and your plans for it sound solid.
 
I've not monkeyed around with editing out plosives like that, I've used windscreens, which are frankly a pain. On my voice, losing some high end is not an issue, but with a female vocalist of her quality, I take your point.
 
cheers, and good luck going forward!  -Tom

The only critiques I could come up with is a bit of high-end "lip smack" on the vocals here and there, and the piano is a bit dark.   But I understand where you're going with it in context.  So suffice to say, this is something I could listen to repeatedly. 
 

Not being a huge fan of Tom Waits or long, sad songs, I can, nonetheless recognize that this was exceedingly well done.  Loved her voice.