I love the nn [name]Lucy[/name] for [name]Louisa[/name], too. I voted for [name]Louisa[/name] [name]Maeve[/name]. Also loved [name]Louisa[/name] [name]Violet[/name]. Another favorite of mine has been [name]Louisa[/name] [name]Frances[/name].
I just have to say that when I saw the title of this forum my knee jerk reaction, before I had seen any of the names on this list, was [name]Louisa[/name] [name]Joy[/name]. I also like [name]Louisa[/name] [name]June[/name] and [name]Louisa[/name] [name]Blythe[/name]
I like [name]Louisa[/name] [name]Charlotte[/name] and [name]Louisa[/name] [name]Corrine[/name].
[name]Louisa[/name] [name]Corinne[/name] is lovely!
[name]Corinne[/name] is best. I also like [name]Violet[/name] ok. [name]Joy[/name] is wonderful.
[name]Louisa[/name] [name]Violet[/name] & [name]Louisa[/name] [name]Iris[/name] have my vote.
[name]Louisa[/name] [name]Charlotte[/name]!!! Gorgeous. The perfect combination of antique-ish and modern. I prefer [name]Louisa[/name] to [name]Lucy[/name], but you’re right on point in creating combos for each – they are such different names and one will surely fit her. [name]Love[/name] [name]Annabelle[/name] [name]Rose[/name], by the way. 
These will be well-named little girls.
[name]Louisa[/name] [name]Corrine[/name] is by far my favorite. I [name]LOVE[/name] the way [name]Louisa[/name] sounds paired with the accented last syllable on [name]Corrine[/name]. When I was considering [name]Louisa[/name] for my own baby I had it paired with [name]Marguerite[/name] (a family name). Another name I can think of with that similar flow is [name]Louisa[/name] [name]Delphine[/name].
I think [name]Louisa[/name] [name]Charlotte[/name] is the best by far, but I do like all of your middle name choices.