How about this for a Bat Mitzvah celebration:
Hold it the first Friday night after the girl turns Bat Mitzvah. Have women in the community (and only women) stand around and say “amein” as the Bat Mitzvah girl lights candles in her home as a chiyuv for the first time, and follow it with a festive women-only meal where the Bat Mitzvah girl makes kiddush and motzi, offers divrei Torah on the parsha, and leads the zimun?