i know of a family whose [name_f]Rosemary[/name_f] has an extremely unique, botanical middle name, which sounds like it would be too match-y, but actually works surprisingly well. it feels earthy, and so fairy-like as a combo 
some assorted ideas…
[name_f]Rosemary[/name_f] [name_f]Edith[/name_f]
[name_f]Rosemary[/name_f] [name_f]Aviva[/name_f]
[name_f]Rosemary[/name_f] [name_f]Selah[/name_f]
[name_f]Rosemary[/name_f] [name_m]Hopestill[/name_m]
[name_f]Rosemary[/name_f] [name_f]Praise[/name_f]
[name_f]Rosemary[/name_f] [name_f]Lark[/name_f]
[name_f]Rosemary[/name_f] [name_f]Fern[/name_f]
[name_f]Rosemary[/name_f] [name_f]Joy[/name_f]
[name_f]Rosemary[/name_f] [name_f]Ruth[/name_f]
[name_f]Rosemary[/name_f] [name_f]Hosanna[/name_f]
[name_f]Rosemary[/name_f] [name_f]Bliss[/name_f]