Sandra,

I've listened to your sample 4 times now. And it's so obvious that you can carry a tune, so that's good -- but don't fear that your voice lacks a certain "perfection" of sorts.

You might just need to embrace the "Übung macht den Meister" concept when it comes to honing your voice, and the impression you want to make, vocal coach or not.

I retrieved some youtube examples of female singers who you might want to listen to.

(I hope this is okay with the rules & regs?)

Karen Carpenter's lone-ish vocal for "Masquerade"
https://www.youtube.com/watch?v=lKy77tpT_do

The full album version:
https://www.youtube.com/watch?v=ljWyIKyua8c

Fiona Apple, Extraordinary machine recorded
https://www.youtube.com/watch?v=T14ux2k7rk0

Fiona singing it live:
https://www.youtube.com/watch?v=YsMZkCLxfkM&feature=related

Phoebe Snow singing Harpo's Blues
https://www.youtube.com/watch?v=0SESmndcKI0

Janis Ian has a higher register than you, but this might be illustrative:
https://www.youtube.com/watch?v=VMUz2TNMvL0&feature=related

Basia sings higher & lower, instructive vocals
https://www.youtube.com/watch?v=sMmY70RPI24

Tracy Chapman sings Fast Car live
https://www.youtube.com/watch?v=Orv_F2HV4gk

Norah Jones' Cold Cold Heart, live
https://www.youtube.com/watch?v=g35zS1tVO3o

... and Come Away with Me
https://www.youtube.com/watch?v=c1V5Wk9gb4U


These female singers may not represent your style, but hearing their takes on those tunes might offer something in the way of practice.

Cheers,
Christa