Of the two, I prefer Vivienne Noel--however, if you're going for the pronunciation Noelle (the feminine name) I I prefer it spelled Noelle. Noel is a male name to me--Noel Gallagher, Noel Coward, Noel the character from Felicity.
This. Vivienne is beautiful. Gabriela is pretty, too. The only component I really dislike is Brooklyn. It always makes me cattily think "oh, is her sibling's name The Bronx?"