I think I'm just about even between
Cassandra and
Kassandra; I don't know much about Greek names, but I think aesthetically they're on a par with each other.
Lysandra is probably one of my favorites that I've seen so far. I tend to like L names. I think Isandra would be feasible, too;
Isandro is listed in the database but I'd take the leap and feminize, no problem. :-)