I was about to suggest [name_f]Amabel[/name_f], and it has already been suggested. Gorgeous name. 
Other suggestions:
[name_f]Liana[/name_f]
[name_f]Amelia[/name_f]
[name_f]Miranda[/name_f]
[name_f]Stella[/name_f]
[name_f]Arabella[/name_f] - as a variation to [name_f]Arabelle[/name_f], you could get the nickname [name_f]Bella[/name_f].
[name_f]Lilia[/name_f]
[name_f]Lydia[/name_f]
[name_f]Eva[/name_f]
[name_f]Isabelle[/name_f] - it is popular, but not more than [name_f]Olivia[/name_f] and I love this name.
[name_f]Marcella[/name_f] - you could get [name_f]Ella[/name_f] as a nickname, similar to [name_f]Bella[/name_f].
[name_f]Adelaide[/name_f]
[name_f]Hope[/name_f] this helps! Sorry for any repeats.
I read somewhere that names like [name_f]Elizabeth[/name_f] and [name_f]Alexandra[/name_f] are ideal for [name_u]Gemini[/name_u] since they offer lots of different nicknames to suit their ‘multiple’ personalities - [name_f]Liz[/name_f], [name_f]Libby[/name_f], [name_u]Lisa[/name_u], [name_f]Elsie[/name_f], [name_f]Eliza[/name_f], [name_f]Bess[/name_f], [name_f]Betty[/name_f], [name_f]Beth[/name_f], [name_f]Ellie[/name_f], etc etc etc and [name_f]Alexa[/name_f], [name_u]Alex[/name_u], [name_u]Allie[/name_u], [name_u]Sandy[/name_u], [name_m]Xan[/name_m], [name_u]Lexie[/name_u], [name_f]Dree[/name_f], etc. Following this logic, I think [name_f]Mirabelle[/name_f] is your best option since it gives her room to be [name_f]Mira[/name_f], [name_f]Miri[/name_f], [name_f]Belle[/name_f], [name_u]Mel[/name_u]… not that I wholeheartedly believe in astrology, only somewhat. 
I like the suggestion of [name_f]Amabel[/name_f], too.
Since you seem to like -ella and -bel- names, a few other ideas:
[name_f]Marella[/name_f] - I associate this with the Italian princess [name_f]Marella[/name_f] Agnelli.
[name_f]Christabel[/name_f]
[name_f]Claribel[/name_f] - appears in [name_m]Shakespeare[/name_m]'s The [name_f]Tempest[/name_f] and [name_u]Spenser[/name_u]'s The Faerie Queene (in which [name_f]Claribell[/name_f] is “the fairest Lady then of all that living were”); there’s also Clarimonde and Clarissant.
[name_f]Corabelle[/name_f] or [name_f]Corabel[/name_f] - reminiscent of coral bells, a type of flower (genus Heuchera). I actually prefer [name_f]Coralie[/name_f] and [name_f]Corisande[/name_f].
Betzabel - variation of Betsabé/Betsabea/Bethsabée, international forms of [name_f]Bathsheba[/name_f].
Maristella - comes from Stella Maris, a title of the Virgin Mary meaning “star of the sea” in Latin.
And since you like [name_f]Arabelle[/name_f], there’s also [name_f]Arianwen[/name_f], a Welsh name.
I was also going to suggest [name_f]Amabel[/name_f] (A pronounced “ah”). [name_f]Amabel[/name_f] could go by [name_f]Belle[/name_f]/[name_f]Bella[/name_f]. Similarly, the name [name_f]Mabel[/name_f] popped in my head. [name_f]Mabel[/name_f] is cute like [name_u]Bailey[/name_u], without the dog-associations.
Both [name_f]Amabel[/name_f] and [name_f]Mabel[/name_f] mean lovable, which is pretty perfect.
I apologize for the delay in responding. Thanks all of the wonderful suggestions. I took lots of notes
Much appreciated!!
[name_f]Marella[/name_f] is an interesting name. [name_f]Ella[/name_f] as a nickname sounds beautiful. I’ll ask what my wife thinks.
Also, thoughts on the name [name_f]Ellie[/name_f]?? Are there many [name_f]Ellie[/name_f]'s out there in your social circle? I personally am out of the loop since I’m not a member of the “young” generation anymore nor am I around teens much.
[name_f]Ava[/name_f]- I know plenary [name_f]Ava[/name_f]'s, so the name doesn’t really appeal to me anymore…
[name_f]Olivia[/name_f]- I know a few [name_f]Olivia[/name_f]'s, but I adore the name, an it’s nicknames.
[name_f]Arella[/name_f]- I’ve never heard this name before! It’s really beautiful. I prefer the short a too.
[name_f]Bella[/name_f]- I agree, best as a nickname, but stands for its own aswell.
[name_f]Arabelle[/name_f]- nice, however I prefer [name_f]Arabella[/name_f] (you can use the nickname [name_f]Bella[/name_f])
[name_f]Mirabelle[/name_f]- [name_f]Mirabelle[/name_f] is really pretty, and very underused! The [name_f]Mira[/name_f] part isn’t my favourite, but it would differ with nicknames
[name_u]Bailey[/name_u]- My [name_m]Friend[/name_m] is [name_u]Bailey[/name_u], and I love the name! It’s a strong and hasn’t been getting a lot of attention lately.
[name_u]Logan[/name_u]- I like this name on a girl, but I prefer it on a boy. I could see this name working for a girl though.
Good luck!!!
I know 2 [name_f]Ellie[/name_f]'s. The name is really beautiful.
Here are names you might like. Sorry for repeats:
[name_f]Eve[/name_f]
[name_f]Violet[/name_f]
[name_f]Isabel[/name_f]
[name_f]Amalia[/name_f]
[name_u]Vivian[/name_u]
[name_f]Belle[/name_f]
[name_f]Audrey[/name_f]
[name_f]Ivy[/name_f]