[name_u]Jess[/name_u] and [name_u]Brooke[/name_u] are family names that are in consideration.
So [name_f]Della[/name_f] [name_u]Jess[/name_u] and [name_f]Della[/name_f] [name_u]Brooke[/name_u].
We have a three syllable surname starting with a [name_f]MAY[/name_f] sound, so I think a shorter middle name would sound better, but Iām open to suggestions.
I also like [name_f]Della[/name_f] [name_f]Charlotte[/name_f] 
[name_f]Della[/name_f] [name_u]Brooke[/name_u] sounds choppy to me. I feel like [name_f]Della[/name_f] [name_u]Brooklyn[/name_u] would soften it.
[name_f]Della[/name_f] [name_u]Jess[/name_u] seems too short, and choppy to me.
[name_f]Della[/name_f] [name_f]Charlotte[/name_f] is my favorite. A nice mix of modern and classic.
[name_f]Della[/name_f] [name_f]Scarlett[/name_f]
[name_f]Della[/name_f] [name_f]Faye[/name_f]
[name_f]Della[/name_f] [name_f]Claire[/name_f]/a
[name_f]Della[/name_f] [name_f]Katherine[/name_f]
[name_f]Della[/name_f] [name_f]Evangeline[/name_f]
[name_f]Della[/name_f] is certainly a favorite of mine. So glad to see her here :)!
More middle ideas:
[name_f]Della[/name_f] [name_f]Fern[/name_f], [name_f]Della[/name_f] [name_f]Florence[/name_f], [name_f]Della[/name_f] [name_f]Frances[/name_f], [name_f]Della[/name_f] [name_f]Francine[/name_f], [name_f]Della[/name_f] [name_f]Maeve[/name_f], [name_f]Della[/name_f] [name_f]Margaret[/name_f], [name_f]Della[/name_f] [name_u]Ruby[/name_u]
Would [name_f]Della[/name_f] [name_f]Jessamine[/name_f] work? That sounds a bit less choppy then [name_f]Della[/name_f] [name_u]Jess[/name_u]. [name_f]Della[/name_f] [name_f]Rose[/name_f] is what I would suggest.
[name_f]My[/name_f] first thought was [name_f]Della[/name_f] [name_u]Ruby[/name_u]