I've got some issues with
Cassandra and
Constance: the full names are gorgeous, but nicknames are not my cup of tea, not at all...
Cassandra Lily - pretty and romantic
Cassandra Juliette - this one has a bit tragic, or rather darkish aura.
(I think about Cassandra - Trojan princess, and Juliet* Capulet)
*If I'm not mistaken it's
Juliette in French (
Roméo et
Juliette)