Singer-Songwriter isn't quite the right fit, nor is 'composer'. Debbie may not have been the first songleader, but she turned it from something that was done strictly at camp into the way many Jews experience prayer. In large measures, she helped bring camp-style and more casual worship to the synagogue, integrated Hebrew with English in a Reform movement struggling with how to blend the two, feminized the liturgical voice to a large degree, and, well, gave the last couple of generations of Jews permission to experience prayer as joyful .
She could be prickly (Shir Ami members will remember when she yelled at the delegation at the 2003 URJ Biennial because they were DANCING TOO SOON), and I've talked to many cantors and rabbis who disliked her music for this reason or that, but no one can doubt the influence she's had on worship in the 20th-21st centuries. Before her, there might have been prayer, but certainly not spirituality. The idea of offering a healing prayer in a Reform synagogue was simply bizarre before Debbie. She gave a generation of seekers a voice. I'll quote Cantor Rosalie Boxt from the above article:
“The reason so many around the world feel close to Debbie, and call her “friend” is because she, in leading worship or performance, gives us permission to feel deeply,” Boxt said. “She gives fully of herself and has opened a door for many to share their deepest hurts or their purest joy. She asks people to be open to their truest hearts, to their longing for the Divine, and for the need we have for love and friendship and for each other. There is no pretense with Debbie, and her music and spirit have created a growth in expression in Jewish music, liturgical and non, that speaks to a Jewish community that wants to be fully engaged in prayer, in song, and in learning.”Without Debbie, Jewish music and Jewish prayer would look very, very different. You can't go to a service in almost any movement without hearing her melody--from her Havdallah to shehecheyanu to so many others. And I would argue that our spiritual and musical experience would be poorer had it not been for that kid writing music at Olin-Sang Ruby and Kutz camp.
In remembering her, everyone is quoting from her "Miriam's Song", most especially because she died as we begin the reading of that Torah portion that deals with the song of the Sea, Parashat B'shallach. But I think another Torah portion-related song fits the moment better: her song on parashat Lech Lecha. So I'll leave you with the last stanza:
Lechi lach and I shall make your name great
Lech li-cha and all shall praise your name
Lechi lach to the place that I will show you
Li-simchat chayim, li-simchat chayim
Li-simchat chayim lechi lach.
And you shall be a blessing, you shall be a blessing
You shall be a blessing lechi lach.