Melba is the name of the principal of the all girls' school just down the road from my school. I have several friends at that school, and I only ever hear the name said in jest as they immitate one of her speeches.
Melba does have quite a sweet sound, although I don't find the etymology particularly interesting.
A few suggestions (sorry for any repeats):
Melba HazelMelba SalomeMelba JessicaMelba Dove
Melba Georgette/
GeorginaMelba WinifredMelba AntoniaMelba DorothyMelba JamesinaMelba ZephyrineMelba PeaceMelba ThomasinaMelba OttolineMelba LeonoreMelba ManuelaMelba LaurentineMelba OlivieMelba Sophie