I think they're all lovely together, with the exception of
Ezra and
Sebastian. I think they're both soft, beautiful boys names but in completely different ways from each other. I get more of a independent modern American from
Ezra and a gentle artsy European vibe from
Sebastian. Personally I would use
Ezra and
Simeon, for instance, or
Emil and
Sebastian.
Charlotte and
Nathaniel are a little odd together but I like it! They're the names of two of my favorite classic authors so that ties them together for me.
I think what makes the rest of them work together is they share elements like number of syllables and vowel sounds. They're almost all underused classics too.