She has a nice soothing voice.

You ain't about to catch her belting out powerful notes and doing runs or anything tho. Charlotte Day Wilson seems to be along these same lines from what I've heard.

That said, I've never been a Winehouse fan. Sounds like she can't get control of her mouth to me. I always found her more annoying than entertaining. I think I like 2 of her songs and one of them she didn't write.

Joss Stone can sing, but I never connected with any of her music... actually that's the case for most of the list outside of Nai Palm and Adele. Deborah Jordan and Alice Russell might be the best singers you mentioned imo.

I love Moonchild's aesthetic but ol girl's whispery voice just becomes annoying after so much. It's relaxing for about 5 minutes, but then I'm like gotdamn when are you gonna sing with your WHOLE voice? Lol.