Middle name for Lily...which is best?? :D?

For Lily Potter? If so, you need a name that would have been commonly used in early 60s Britain, so scrap Scarlett, Charlotte, Ava, Mya, Elise, Adeline and Jessamine. They weren't used. If it's your own character, a middle name shouldn't be important. It shouldn't appear in the text unless absolutely necessary, so the name you chose doesn't really matter.