Hmm, I think Eva had a great, pure voice that was not operatic at all, very popish in my view (nothing wrong with that). She also surprised us with her note choices, even though they're very simple. In this way she is like a jazz singer, but she stays to close to the original line that she stays in the pop genre, without getting into the yodelling that's become so popular since Whitney Houston first did it tastefully and then got carried away.
I don't think that people that take solace in Cassady are going to enjoy Barber or Cole so much. Eva was about the upside and joy and those two see mostly the dark side, IME. (I like them, but stay away).
Stacey Kent is a jazzer that stays close to the melody. Her girl-ish voice always gives me a lift. Another pure, girlish voicalist is Erin Bode.
I'm not trying to be disagreeable, just adding a slightly different view.
Dave
