There are some great suggestions here (and on your original list) but I'm surprised no one has mentioned Alison Krauss. My absolute favorite female vocalist. Such an amazing voice with great range and emotive communication.
Definitely recommend Alison Krauss. Specifically 'New Favorite' and 'Forget About It'. I use several of the tracks on these albums as references.
I agree on "Forget About It".........absolute reference quality recording.