I find Vivian, Vienna, and Evelyn too similar in sound (as a pp noted, viVIAN and VIENna with the first; Vivian and Evelyn sound a bit like the same sounds rearranged to me). Rosalind and Felicity are by far my favorites! American Girl is constantly updating their collection. Some older dolls, like Samantha, have been retired, and I imagine that at some point, Felicity probably will be, too, so her generation won't associate them so much (plus it's fun to share your name with the doll you get! She'll know you didn't name her after it). And all that said, I don't associate Felicity with the doll... And Rosalind is beautiful, historical, literary, etc. Fabulous. Mirabel is fine; it just doesn't wow me.
Agree with everything said here! I think Rosalind would be my first choice, then Felicity.