Hi. I'm new here. I've been around the boards for ages (RHF, etc) but retired away from the last year or so.
Anyway, it was funny because before even seeing any of your responses, Holly McNarland was exactly who came to my mind. All of your have included many good reasons why so I won't add on.
Another could possible be Ani DiFranco. Both for reasons of the folk roots mixed with political messages and their own styles of singing. That's where the similarities would end I suspect.
Otherwise, Holly McNarland has my vote.
Cheers
~A
