You have some wonderful names on your list. My mind works in styles or sibsets so I'll group them as follows.
Continental Feminine Flair
Penelope - lots of images come to mind: the mythological wife patiently waiting for her husband's return, British actresses of screen and stage (Ms. Kendall and Keith), a Spanish actress (Cruz) and unfortunately, a Kardashian baby. (Yellow)
Genevieve - the patron saint of Paris is my first image. A chic French lady with hat and clothes. (Royal Blue/Purple)
Francesca - an exotic and lively Italian lady who lives each day to the fullest. (Burnt orange)
Vivika/Viveka - I prefer the Viveca spelling. For some reason, this name always reminds me of a cool Scandinavian winter.(White)
Eliza - spunky Ms Doolittle comes to mind. Fiery and sassy. (Red)
Eve - the name of Adam's better half is one of opposites: its sweet but with an edge, it's simple but sophisticated. (Green)
Calla - the mysterious and dreamy flower (White)
Briar - harsh and prickly plant and Sleeping Beauty. (Black)
Saffron - this word makes me think of the Buddhist monks who wear robes of this colour. (Orange-red)
Tatum - Tomboyish, spunky and full of fun. I've heard of Tatum O"Neil and Channing Tatum (woman and man). (Amber)
Afton - I think of the river and the Robert Burns poem (Silver)
Brighton - I've been to this English seaside town so I have a "sunshine, merry-go-round and cotton candy on the Pier" image. What happy memories! (Blue)
Penelope--could've been Persephone
Genevieve--so pretty in French, but how to make everyone pronounce it that way?
Eliza--Eliza Jane, cute--like Clementine
Tatum--brat I used to babysit, but also precocious, gifted child
Afton--made-up? it's not too bad
Brighton--child actor from Family Matters...I only remember because I liked the name, but now it seems dated.
Penelope- I think of Ulysses & I think of the Kardassians & I think of Penelope Cruz as well. A lot of nickname options. Honestly, I've always thought of Penelope the same way that I think of Olive. A quirky choice that manages to be a bit pretty & a bit ugly...the only thing is both of these names are quickly losing the quirk factor as they gain popularity/celeb following.
Genevieve- I love the nn Jenny, but not so much with the G. It looks off to me. It's a pretty sounding name, but it doesn't thrill me. I must say though, every adult I've known with this name has been a really rad girl!
Francesca- Feels dramatic & sexy
Vivika/Viveka- I think of the actress Vivica A Fox. It's a rare name so that's my only association to it. Pretty sounding, but sounds like a Vivian/Jessica smoosh
Eve- LOVE the sweet simplicity of this name.
Eliza- I really love this one as well. It is a bit less neutral than Eve
Calla- I want it to be short for something even though it's pretty on it's own. Calliope?
Briar- It's OK. I think of a thorny bush. I like nature names, but I don't know if I like the sound. If I think about it for a moment I also think of icecream.
Saffron- Too foody for me.
Tatum- This is a cute name. I'm surprised I don't hear it more. I like it.
I like all the rest. Good luck :)
I love Eve, Genevieve, and Francesca.
I dislike strongly the three unisex names (although there are unisex names I like). Brighton and Afton seem like boys. I also think that sisters named Tatum and Francesca would probably be jealous of each other and seem odd.
I really like Vivika, Penelope, and Eliza even though I wouldn't use them myself.
I dislike mildly Calla, Briar and Saffron although there are nature names I like. Both Calla and Briar seem like half a phrase with the whole phrase being Calla Lily and Briar Rose. Also Briar I believe means thorny but I could be wrong. I like Saffron the best, but I would prefer Sage, Rosemary, and Lilac to name a few. Also Lavender fits in well with the other names.
I think all of these names are usable except Afton.