If your boys have trad names would you not want something similar? If I were your daughter I'd be a bit pissed off if all my brothers had solid names and I got Lottie or Mollie as a full name..
Anna, Susannah, Shoshana, Elizabeth, Elsbeth, Naomi, Frances, Francesca, Eleanor, Helena, Julia, Louisa, Serena, Claudia, Jessica, Miranda, Abigail, Adela, Beatrice, Meredith, Marianne, Caroline, Joanna, Flora, Lois, Katharine, Jocelyn, Sarah, Isabel, Laura, Cecilia, Honor, Victoria, Rachel, Juliet, Charlotte, Stella, Emma, Verity, Constance, Edith, Hannah, Sophie, Marina, Jennifer, Clio, Jane, Grace, Philippa, Oona, Phoebe, Eloise, Adelaide... there are a lot of girls names..