Wow thank you so much for your responses everyone! I like a lot of the ideas, my favorite possibilities are:
[name]Cornelia[/name] “[name]Nell[/name]” I really like this but I already have a character named [name]Nell[/name].
[name]Eleanore[/name] “[name]Elle[/name]” is cute but I think [name]Elle[/name] is too feminine, or maybe too [name]Elle[/name] Woods for a blonde character.
I love [name]Antoinette[/name] and [name]Andie[/name] but I think [name]Andie[/name] is a little too playful. I need something more serious.
[name]Nicolette[/name] is one of my favorites and I love the suggestions of [name]Nic[/name] and [name]Colt[/name], but I think [name]Nic[/name] might be too generic and [name]Colt[/name] is too country.
[name]Georgette[/name] is another one I love for her, but don’t think any nickname fits.
I really like [name]Toby[/name], but can’t think of a full name (I can’t use [name]October[/name] for this character, maybe for another book though, it’s very cool.)
[name]Francesca[/name] is one of my favorite suggestions, but [name]Chess[/name] and [name]Frankie[/name] don’t feel quite right.
[name]Liv[/name] is a great nickname, but I dislike the popularity of [name]Olivia[/name]. Maybe [name]Lavinia[/name]? .
[name]Love[/name] [name]Theodore[/name] “[name]Theo[/name].” Definitely a possibility. [name]Toby[/name] might even work for [name]Theodore[/name] as a stretch.
[name]Romy[/name] or [name]Remy[/name] would be great for her (I actually love these!) but too many similar sounds of her best friend’s name.
[name]Wilhelmina[/name] is love! Unfortunately one of my other characters is [name]Willa[/name].
I really like [name]Penelope[/name] for her, I think I’d use [name]Penn[/name] ([name]Poppy[/name] is my favorite for [name]Penelope[/name] but doesn’t suite her).
[name]Genevieve[/name] is great, but don’t like any of the nicknames for her.
[name]Cordelia[/name] is awesome and I do really like “[name]Cordy[/name].” I worry though that it’s too playful for her.
[name]Clementine[/name] and “[name]Lemon[/name]” are really cute! That is a close fit. [name]Lemon[/name] reminds me of [name]Hart[/name] of [name]Dixie[/name] though, that’s the only place I’ve ever heard it, and that [name]Lemon[/name] and my [name]Brett[/name] have a couple similarities.
I like [name]Quinn[/name], but is it too Glee? Maybe [name]Quincy[/name]. But I don’t like [name]Quintessence[/name], would [name]Jacqueline[/name] work in a stretch?
[name]Juliette[/name] would be wonderful. I’d use “[name]Jett[/name]” but that starts with a J, which I’d like to avoid. Ette/[name]Etta[/name] is cute, and while I love it I think it’s too old fashioned for her nickname.
[name]Reese[/name] is another nickname I love even though it starts with an R which I wanted to avoid. I’d consider it if I found the right full name.
I love [name]Katharina[/name] and [name]Kit[/name]. But is [name]Kit[/name] too close to all the [name]Kat[/name]/[name]Kate[/name]’s in YA lit these days?
I love the suggestions for [name]Rhett[/name], that would fit perfectly, but my little brother is named [name]Rhett[/name]. He was mad that I used the similar [name]Brett[/name] for a girl, lol!
The suggestions that are closest to what I’m looking for are:
Nicknames without a full name that fits: [name]Toby[/name], [name]Liv[/name], [name]Quinn[/name]/[name]Quincy[/name], [name]Reese[/name]… but I’m not sure that any are quite, I don’t know, classy enough?
Names I like but don’t have a nickname that fits: [name]Nicolette[/name], [name]Georgette[/name], [name]Juliet[/name]/[name]Juliette[/name], and [name]Katharina[/name].
The ones with both full name/nickname potential: [name]Penelope[/name] “[name]Penn[/name],” [name]Cordelia[/name] “[name]Cordy[/name],” [name]Clementine[/name] “[name]Lemon[/name],” though I still have reservations about all of them.
I do still like [name]Isobel[/name] [name]Victoria[/name] “[name]Ivy[/name]” but is [name]Ivy[/name] strong and snappy enough?
Geez it’s hard to rename a character you’ve spent years with!! Thanks again everyone! If you have any more ideas please post!