Interesting list OP. My picks would be Flora or Merryn, with Ariadne as a wild card as it’s a bit of a risky one!
Ariadne - 7/10, it’s beautiful, but a lot to live up to. There was one on my year at school who really didn’t (gawky, awkward teen with greasy hair and NHS specs) and she was teased relentless for the contrast between her name and her image.
Rosa - 6/10, used to love this but it’s recently become much more popular and now blends into a pool of similar names
Edith - 5/10, I find it a little harsh, and Edies are two a penny
Isidora - 5/10, I can see objectively that it’s pretty, but it’s too frilly for me
Matilda - 4/10, a bit dull and overdone
Flora - 9/10, love this
Claudia - 7/10, like it, very classy and elegant, but I find the meaning a little off-putting
Therese - 3/10, not keen
Merryn - 9/10, lovely
Theodora - 4/10, a bit long and flouncy for me
Valentina - 4/10, ditto