I can’t comment on which are rarest, though I have encountered [name_f]Aviva[/name_f], [name_f]Dafna[/name_f], [name_f]Raisa[/name_f], [name_f]Esther[/name_f] + [name_f]Ester[/name_f], [name_f]Reina[/name_f], [name_f]Elisheva[/name_f], [name_f]Rivka[/name_f], [name_f]Nava[/name_f], [name_f]Shoshana[/name_f], [name_f]Miriam[/name_f], and [name_f]Elke[/name_f] in ‘the real world’ if that’s anything to go by.
My personal favourites are… (with nicknames)
Liraz (Raz, [name_f]Lira[/name_f], Liri, [name_f]Lizzy[/name_f])
[name_f]Raizel[/name_f] (Zella, [name_f]Rosie[/name_f])
[name_f]Golda[/name_f] (Goldie)
[name_f]Bluma[/name_f] (Blu)
[name_f]Shoshana[/name_f] (Shani, [name_f]Sasha[/name_f])
[name_f]Nava[/name_f] (Nav)
[name_f]Miriam[/name_f] (Mim, [name_m]Mims[/name_m], [name_f]Mitzi[/name_f])