I like
Emilie. It looks more "dainty" than
Emily. Like an
Emily would maybe be a cheerleader, while an
Emilie would be an artist or a poet and probably have a more whimsical personality. I can see the appeal of
Emily too though, in the more classic sense. I'm just slightly biased against it because of how popular it was in my generation.
Emilie also reminds me of
Emilie Autumn. (I like her but if you don't, or have no opinion, it still works because the association isn't so strong that it's the only thing I can think of when I see the name. It's just the name primarily.)
Emilie seems more feminine and maybe more "pale". If they were both little girls hanging out in someone's backyard,
Emilie would be the one sitting there drinking tea under a parasol while writing poetry and
Emily would be skipping around, rolling down hills and picking flowers.
I like
Violet Emilie, but not
Marlowe.
Marlowe is the opposite of dainty, so I don't think it goes all that well with
Emilie.
I'd use alternate spellings of a popular name, as long as the spellings weren't too unknown.
Vivienne (although I pronounce that different from
Vivian),
Elisabeth, and
Brook are good. And
Aeron /
Aron for boys. Plus with something like
Emilie, it's less of an alternate spelling and more a translation (like
Eric,
Erik, and
Erich.) It's a lot nicer to say "My name is
Emilie, spelled the French way" then "My name is Emmili, with 2 m's and an i". When it's a translation it just feels more 'legit' (and is more likely to be common, even if it's less common than the other form).