Maybe a girls name without an a ending for variety? - Felicity, Jasmine, Margot, Madeleine, Meredith, Verity, Frances, Harriet, Cecily, Genevieve, Marianne, Rose, Robin, Elizabeth nn Beth or Bess
Or if not - Esther, Honor, Flora, Clara, Serena, Claudia, Stella, Tessa, Elizabeth nn Eliza
Boys - a short name or nn might be a good contrast - Max, Hugh, Guy, Theodore/Edward nn Ted, Christopher nn Kit, Nathaniel nn Nat, Nicholas nn Cole, Francis or Franklin nn Frank, Benedict nn Ben, Sam, Dan, Tom as nns. Plus Jesse, Jethro, Jerome, Silas, Rufus
Or something softer to go w Amelia - Lawrence nn Lawrie, Christopher nn Christy, Tobias/Toby, Theodore nn Theo, Miles, Giles, Milo