Yes, I suppose she probably is the voice of a generation, but it's not a great generation for music. I've heard a few of her songs and they're ok - none of the stuff I've heard on the radio has made me rush to listen to a full album. The impression I get (possibly not a fair impression) is that she mostly sings about her romantic relationships. She appears to be pleasant and hardworking.
One artist that really grabbed me growing up was Tori Amos, and I love her still. She's a child piano prodigy who grew up to be a singer-songwriter and has released sixteen albums to date. The first two albums she co-produced, then the rest she has produced herself. She writes all her own songs, and plays piano and other keyboards (sometimes two at once). What grabbed me and pulled me in, apart from the sheer beauty of the music, is the astonishing range of subjects she covers in her songs. She's an unashamed feminist and examines the female experience in incredibly inventive ways. There are songs about the difficulties of growing up, love, loss, grief, being a ghost, rape, Napoleon, female genital mutilation, the Native American experience, Jungian psychology, masturbation, wanting to kill a co-worker, the patriarchy, motherhood, mythology, the American political landscape, psychedelic experiences, the Gnostic gospels, criticism of mainstream religion, criticism of pornography, fame, the Kennedy family, sisterhood, criticism of homophobia, the death of the American dream, and that's just the tip of the iceberg.
Through her music I've been introduced to the writing of Neil Gaiman (one of her albums, Scarlett's Walk is a companion piece to his book American Gods) for which I'll be ever grateful. There are many literary reference in her songs, from Alice Walker, Michael Ondaatje, Henry James to Daphne du Maurier to name just a few. Through her I discovered Joni Mitchell, Stevie Nicks, Leonard Cohen, David Bowie and Carly Simon.
I also love Kate Bush and PJ Harvey, but it's way too late to start on their genius tonight.
Those are my reference points from growing up in the nineties, and I'm not sure that any musicians around today can offer that breadth of experience, to be honest.