Helena Florence is a gorgeous combo, no doubt about it. I can't let go of my "Anna Florence" just yet!
I have a friend whose mother's name is Susan and grandmother's name is Susannah.
I think Susannah just has a more interesting feel and is less dated.
Like the classic version of the trendy "Savannah".
Here's a few ideas:
Susannah Ivy
Susannah Claire
Susannah Phoebe
Susannah Odette
Susannah Abigail
Susannah Pearl
Susannah Beatrix
Susannah Holly
Susannah Colette
Susannah Lucille
Susannah Margot
Susannah Helen
Susannah Caroline
Susannah Michelle
Susannah June
Susannah Laurel
Susannah Bridget
Susannah Faye
Susannah Rosemary
Susannah Adele
Susannah Violet
Susannah Olive
Susannah Elise
Susannah Lillith
Susannah Amelie
Susannah Carys
Susannah Eleanor
Susannah Primrose
Susannah Avril
Susannah Ruby
Susannah Charlotte
Susannah Emilie
Susannah Gwendolen
Susannah Adeline
Susannah Mary
Susannah Bronte
Susannah Kathryn
Susannah Mathilde
Susannah Adelaide
Susannah Rachel
Susannah Corinne
Susannah Marguerite
Susannah Willow
Susannah Clementine
Susannah Fleur
Susannah Lillian
Susannah Maeve
Susannah Audrey
Susannah Lorelei
Susannah Rosalyn
Susannah Maud
Susannah Gail
Susannah Romy
Susannah Imogen
Susannah Vivian
Susannah Delphine
Susannah Lois
Susannah Cadence
Susannah Penelope
Susannah Briar
Susannah Meredith
Susannah Juliette
Susannah Alice
Susannah Poppy
Susannah Miriam
Susannah Darcy
Susannah Avis
Susannah Prudence
Susannah Kelly
Susannah Mercy
Susannah Noelle
Susannah Ruth
Susannah Blythe
Susannah Evie
Susannah Maris
Susannah Jacqueline
Susannah Blanche
Susannah Gracie
Susannah True
Susannah Mabel
I think I'll be using Susanna, especially as a first name, because though either is acceptable and Susannah does look prettier, I'd prefer to cut down the first name for efficiency if I can. Why make a kid use 8 letters if the 7 spelling is just as good? I have a 7 letter first and I wouldn't mind having it shortened to Hether if it didn't look so ugly. LOL.
Susannah Ivy - I love Ivy so much. So much. My only nitpick is that Lily Ivy seems a bit overly floral.
Susannah Claire - Rob's younger sister goes by Claire. Can't say I've ever been able to get the Heroes character out of my head. 
Susannah Phoebe - this used to be on my list. Still a fave. Rob strongly dislikes -ee ending names, though. He dislikes Phoebe and Penelope, though not Daphne.
Susannah Odette - sure you aren't reading my list? I <3 Odette, my only issue with it is that nobody else seems to.
Susannah Beatrix - For some reason, the X in Beatrix always seems to extra-clash with any name with strong S's.
Susannah Holly - same nitpick with Ivy. Lots of floral stuff. And with my name being a shrub...
Susannah Colette - A friend of mine has this as a middle name. Somehow I always think of toothpaste
Susannah Lucille - I think of the grandma in Arrested Development. Surprisingly, this is a plus. Only problem here is the C sounds like an S.
Susannah Margot - I've always liked Margot. I think I slightly prefer Margo. No... wait.... I honestly don't know which I prefer.
Susannah Helen - I realllly like the idea of using Helen. I just like Helena too much, though. Also, I think it has potential old-lady feel, if not with a really cool first name.
Susannah Caroline - Sweet Caroline. I <3 it, and the similar Coraline with has more spunk. Rob's sister has this as a real first name. Caroline Claire, goes by Claire.
Susannah June - Ugh, June, you kill me. I love you, but worry for your simplicity. Do you need more? Should you be Juno or Juniper? Ugh, no, neither is as pretty! But you are soooo short for me! Ugh.
Susannah Laurel - that new show Arrow has killed Laurel for me. Hearing it said out loud so much...
Susannah Bridget - Bridget is one of my favorite middle names. It also happens to be one Rob really dislikes (along with Lillith)
Susannah Faye - I kinda like Faye... but I first think of Morgana Le Fay, enemy of Kind Arthur
Susannah Adele - Adele is one of my favorite middle, but I do try to avoid the -a ending/beginning conflict
Susannah Avril - same as above. I do like Avril... I worry about Advil confusion
Susannah Ruby - Ruby.. I like as a middle name. I just fear it will take over popularity-wise and that just makes it less interesting.
Susannah Corinne - I like Corinne, I just like other Cor- names more. Cora, Cordelia, Coraline.
Susannah Audrey - I've found Audrey increasingly pretty over the years. Ever watch Haven? It's has a nice simple beauty, but same as Ruby, I just don't find it as interesting.
Susannah Rosalyn - oooh. I like Only problem with this is the strong S's.
Susannah Gail - interestingly, Gayle is my mother's middle. Never really considered the Gail form. Hm.
Susannah Romy - I like the idea of Romy as a middle, I'm just not sure it sounds enough like a full name. Feels a bit nicknamey.
Susannah Imogen - Pretty! My only issue is the length.
Susannah Vivian - same as above, though I also worry for Vivian's popularity
Susannah Delphine - I really like Delphine as a mythological name.
Susannah Miriam - I really like Miriam. My only worry is that it highlights the stuffier side of Susannah.
Out of what you suggested, I definitely like Susannah Odette. I just... fear using something so out there that I'm sure will make people think I'm trying to hard to be cool or upperclass. Which I probably am.
I shall take this as a compliment.UH! So hard to decide
Thanks for your votes Katie and MeganMoxie! I'll compile them in a bit.
