Elysia (Lissy), Harvey and
Selena is my favourite- pretty name.
Madeleine would be my second choice - I like Maddie as a nn.
Faye would be my third choice but it feels a bit dated to me, especially with your more modern sounding sibling names. Also my grandparents used to say “she’s a bit fay” to mean a bit shy / flaky. Although this generation probably wouldn’t think that!
Lucia has too many pronunciations.
Vienna is a just a place name to me.
Felicity - the one I know goes by Lissy and I don’t like the other nn options.
How about Fern, Serena, Lucy, Vivienne, Violet, Sienna, Leona,