Do you know the middle names of any of your children's friends? Or your own? (unless you went to their weddings?). Prefer Ann, but really, I wouldn't agonise. Choose something that you have a family connection/regard for.
bellissima - yes! Certain family members call me only by my middle name and always have done. Middle names have always been important in our family, and I always ask people what their's is/are. It's a talking point - sometimes the names are boring, but something you can find things out about a person which you never would have otherwise.
They all sound fine - but I agree that the middle name shouldn't start with a vowel. I prefer the names that end with a different sound too. So for me the best names are Bronwen, Jasmin and Rowan. All three are lovely - I would go for the one with the strongest personal meaning.