I don't see the 20's vibe for
Neva, despite its stats. I think it's because it reminds me strongly of 90's actress
Neve Campbell. I've only ever seen a Nev- name on her so it's a tough association to break! Also never come across Maida so it sure could be a 20's name but I am totally Maida ignorant.
Milly,
Vera and
Ruby for sure have the flapper vibe.
I've been thinking of
Millaray Edith and I think you're right - I might tweak it to
Millaray Edie to add some zip.