Sibling Name Help

I have a daughter named [name]Emmeline[/name] (with the “line” pronunciation) and we are expecting another girl.

So far we have [name]Isabel[/name] and [name]Gabrielle[/name] as our name choices. I am leaning one way, and my husband the other. We call our daughter mostly [name]Emmeline[/name], but sometimes [name]Emme[/name]. I prefer using full names most of the time, but I know how names get shortened so I like the possibility of nicknames and I don’t suspect it will be any different with [name]Isabel[/name] or [name]Gabrielle[/name] ([name]Izzy[/name] or [name]Gabi[/name], or [name]Elle[/name]).

I have tried so many names that have gotten vetoed by my husband, but I like classic, more old fashioned names and worry about the fact both of these names are not quite as unique as [name]Emmeline[/name].

Thoughts?