From your list I like
(mainly because of the slightly simpler spellings!)
I would also suggest
Hestia (maybe more domestic than you want, but a very warm, significant goddess)
Antigone (a bit tragic, but stands up to everyone for what she believes in)
Andraste (a Celtic goddess called on by Boudica when she was fighting off the Romans)
Auto correct. Meant serafina
Isolde was not only beautiful, but brave to have forbidden love and was faithful to her heart, if not to her husband.
If you like Jezebel, why not Jael? She lulled an enemy king to sleep in her tent then hammered a stake through his head. I agree with the previous poster that said beauty is not the best or only virtue; cunning and bravery are better than beauty in my humble opinion.
I'm loving Hypatia and Pandeia from your list. Amazon warrior women, Helen, Freya, Theadosia (oops, th), and Mulan (means Magnolia) came to mind reading your post. I can't wait to see what you pick!
Circe, Cleopatra, Hermione, Isolde, Morgana, Serafina and Zenobia are all really great names that I think would go great with Aphrodite. Zenobia especially peaks my interest, and I think either Zen or Bee could be cute nns. As for Jezebel, I'd recommend Googling a blog named Jezebel... they mainly talk about feminist and sexual topics. It was quite popular among my classmates, so I think it would be a good connection to at least be associated with...
I am loving Atalanta, Ceridwen, Circe, Morgana, Serafina, and Xenia.
From your middles I really love a lot of them! Aradia, Brigid, Cressida, Daphne, Eos, Eowyn, Giselle, Isis, Lamia, Niamh, Noor, Olwen, Ophelia, Phoebe, Selene, Signe, Sybilla, Ursula, Vanessa, Villanelle, Yvaine, and Zephyrine!
I like pps suggestions of Ariadne, Vesta, Ondine, Cassiopeia, Nerissa, Rhiannon, Andromeda, Rohana, and Odette.
Morgana made me thing Morgaine, which is also very pretty. And Melisande.
I haven't got much time right now but I just must stay logged on if I see you posting, Otter. Will let SO amuse Nelly and try to be helpful here ;)
#1 My absolute favorite from your list is Hermione. It has wonderful amount of beauty and also everything to go perfect with Aphrodite - style, mythological association, chick, length... And nickname options take my breath. Just close your eyes and imagine sisters Roo and Minnie. Little Roo and Minnie Mouse. Or Dita and Io. I would drool over if I meet sisters named these, seriously. *And I am not saying this because of Nelly's name, I try to be objectiv;)*
#2 Belphoebe - love it with sis name, -ph sounds go so great. It can make excellent sibling connection and, besides that, you can get Phoebe and Dita for everyday use.
#3 Olympia - I don't think it's too much but interesting name theme. They compliment each other nicely and, also, I would like to meet baby Olympia, it's soo underused. I picture gorgeous Angelina Jolie in the movie "Alexander". Stunningly beautiful, stately and wise...
#4 Serafina - lovely name, used to be my crush but its popularity in States unpleasantly surprises, although I guess it's not that in UK. I like Russian Serafima as well, but something inside says its not your thing, maybe angel connection. Serafina, on the other hand, is pretty safe and different, nice choice anyway. The only thing is that I prefer Seraphina spelling.
#5 Gwenllian - oh, such a nutty way to get to Gwen. I like the princess story as well as name sound. Gwenllian and Aprodite are different to degree they go fine together.
#6 Xenia - pretty Xu here! Lovely name and as a person who knows plenty of Xenias/Ksenias (not in UK/US), I would never confuse it with Xena and guess nobody will either. I remember you mentioned you have Russian origin and it might make a fine nod.
I also like Circe and Isolde much but can't imagine them working with Aphrodite as fine as the ones above. Up to you,of course.
The only two I dislike are Cleopatra and Befana. Cleo is very down to earth for me and, honestly(not trying to be saucy or rude), not upper-class. Nikolai Ostrovsky ridiculated it in his works and, unfortunately, I can't get through. And Befana...Yeah, witches are cool but not this ugly Italian granny. Personally, I wouldn't do it to pretty little baby girl. Beata has similar sound and I like it more.
Bravo for considering Ursula, I would like to see it breaking out the mermaid cage. As for other U-names, I like Urania and Uliana(my childhood love, I wanted to use it so bad when I was 6) with A-dite. There are also Uma, Una, Ulrica, Ualani... But I don't think they fit in your situation.
My vote goes straight to Io-Minnie-Hermione ;)
Ottilie, congrats! :) My favourites are Hermione, Isolde, Serafina, and Sunniva (in no particular order). Olympia, Ceridwen and Tinuviel are great too! Suggestions: Galadriel, Hedwig, Angharad, Ingeborg/Ingvild, Ysaline, Hillevi, Snöfrid (just kidding! GP ;)), Estrid, and Frejdis. And perhaps Valkyria/Valkyrie? Could be really cool with Aphrodite and a nod towards Norway:)
Seeing your love of the mythological names I just have to suggest Nausicaä (nah-se-CA), she was a minor character in the Odyssey and also the main character in the beautiful Hayao Miyazaki film, Nausicaä and the Valley of the Wind. It's around fifteen on my list, but I though you would like it. Good luck!
My favorites are in bold.
Atalanta - Said out loud a few times, this quickly gets contracted to "Attle-anta".
Befana - Sounds distinctly homely next to the mellifluous Aphrodite.
Bellicent - This is probably my favorite name on your list. Elegant and queenly, with a strong, lovely sound. Unusual but easy to spell and pronounce. Perfection. Adore.
Belphoebe - You love this name, so I'm hesitant to criticize it...but Belphoebe (while pretty) sounds to me like a mash-up of two trendy names, Isabelle/Bella and Phoebe.
Bradamante - Like Belfana, I find this clunky, fusty, and far too heavy for a kid to wear. The "Brad" beginning makes me think of a dude-ish frat boy; the "man" sound doesn't help.
Ceridwen - I like this name, but your husband doesn't. You'll also run into pronunciation difficulties, which as someone with an oft-mispronounced name I can tell you is a never-ending frustration to avoid if possible.
Circe - LOVE. This is on my long list.
Cleopatra - Probably the best name on your list to pair with Aphrodite: both strong, smart, admirable women with beautiful and commanding names.
Gwenllian - I like the myth, but most people will hear this as an unnecessary elaboration on Gwen. I prefer Guinevere.
Hermione - Far too strongly associated with Harry Potter. It might be usable again in twenty years, but not now.
Hypatia - The woman herself was amazing, but her name leaves me lukewarm.
Isolde - More pronunciation issues, but worth it for such a gorgeous name. My only concern is that Isolde seems rather sleek and icy next to the hothouse flower that is Aphrodite.
Jezebel - Totally unusable -- and this is from someone who has Elektra on her list. Please don't give your child a name that is literally a synonym for "slut".
Lyonesse - I can only think of this as a city. She'll also constantly have to correct people who think her name is Lioness.
Lysistrata - This sounds like a medical cream to me. Sorry.
Morgana - "Dark and velvety" is the perfect way to describe Morgana. This is the perfect complement to Aphrodite, in both sound and mythological resonance.
Musidora - Fussy.
Nimue - Absolutely lovely in every way. I love the potential nn Nim. My only concern is that Nimue, like Circe, seems a little slight compared to Aphrodite.
Olympia - Fine, but it doesn't sing.
Ourania - Terrible idea. Almost as bad as Jezebel. How about Aurelia?
Pandeia/Pandia - She'll get called Panda. How about Pandora?
Serafina - Seraphina is one of my all-time favorite names. Fiery and beautiful.
Sunniva - Pretty, but without the weight and presence of your other names.
Tinuviel - Tolkien fan that I am, how can I not love this name? That said, the sound is a little, well, metallic, and like Sunniva, Tinuviel seems too lightweight compared to the rest of your list.
Xenia - I think Xena has long passed its moment; I wouldn't be worried that Xenia will be confused with the warrior princess. It's a fine name, but it lacks the strength and rapturous beauty of Bellicent or Morgana.
Zenobia - Clunky, dusty, thoroughly awesome, though probably not the best with airy Aphrodite.