I love
Colombe. In fact, I use it as the mn is a few of my top combos. It's not pronounced col-UMBA though, more like co-LOME. The b isn't totally silent, but it's very subtle.
Fabienne,
Donatienne, and
Virginie are all lovely too. I adore
Genevieve, although I pronounce it more like zhawn-VYEV (2 syllables instead of 3).