One of two
Two of two
Ariel & Miranda
Yes, I actually knew a pair…have no doubt their parents were English teachers!
Limited Editions? With tattoos of 1/2 and 2/2 on their feet?
first off, congrats to you!
I know you said you didn’t want themes, but I’m still partial to Hope and Faith. Nice, old fashioned, and not particularly cutesy, in my mind.
Of course few of the names suggested bother me, and some I like better. Just my first impulse
Thing One and Thing Two.
Well, Jewish tradition is to name children after deceased relatives. You could name each girl from one side of the family. And going a few generations back, you’re more than likely to find classic names.
Huh. My cousins are named Katherine and Elizabeth. Interesting coincidence!
I like the following combinations:
Jennifer & Christine
Samantha & Allison
Melissa & Emily
Mostly just a congrats reply China Guy - congrats :).
Otherwise pretty much what WordMan said. I’m glad you seem to be resisting the temptation to preciousness, which seems to be overwhelming for so many young parents.
My very grounded and non-precious step-brother and his wife named their first Francis after his grandmother. Pefectly appropriate, good name. Old-fashioned enough to be underused, not so archaic as to seem odd. But of course she became “Franny” to distinguish her from said grandmother. And when the second daughter came along, they couldn’t help themselves - Zoe :D. Another good name on its own - but c’mon - wayyy too precious as a pair.
- Tamerlane
China Guy, I think Audrey and Vivian are lovely. And not “trendy” or common or the name of some currently popular TV character.
P.S. Assuming they go with your last name. I would not want my child named Vivian Barsaminiam no matter how much I liked the first name.
Ariel and Zenia
Vivian and Audrey are great.
Starting the names with the same letter can be fine. My brother and I are Andrew and Amy. He goes by Drew, I go by… Amy. To go with that though, my mom had a strict rule about him not being nicknamed Andy.
Miranda (with Andy as a nickname) and Samantha
Veronic and Vanessa
Other names not in pairs:
Annabell
Hafsa
Marrie (I think that’s how it’s spelled, pronounced MAR-ee, not mary)
Molly
Beatriz
Congratulations!
As for names, how about Ada and Zoe?
Pinky and the Brain? 
<g, d, r!>
A friend of the family named theirs Elizabeth and Rebecca.
They were Becky and Betsy as little ones, and have now (as adults) adopted their full names.
Vivian is a boy’s name in my book. Vivienne (which looks odd) is the female version. At least, in french.
How about Rose and Sadie? (From the movie Big Business.)
Isabella
Genevieve
This is the name of my niece. While together they are quite a mouthful, separately they are beautiful names. My niece did not acquire this name until she was 3 months old. A few family friends got together and told my brother that if they didn’t figure it out soon her name would end up being Baby for life. So the suggested names were tried out on the sleeping babe, her father crooned the names to her. When she responded 3 times (by smiling in her sleep) to the name Isabella (my suggestion- Yea!) they knew that’s what her name should be.
Vivien and Audrey are quite nice, but together they make me think the parents are really into movies.
No matter what, you have to make sure they sound good with Supreme Court Justice in front (I’m stealing that from somebody on the boards-- it makes sense to me).
I’ve always liked the name Phoebe.
Francophone here. 
Estelle
Celeste
Isabelle
Antoinette
Isolde
Matilde
Adele