Diana sibling names?

First time poster! My wife and I are having a second child (girl) in February and are struggling with names. We have some good options but aren't totally sold yet.

Our daughter's name is Diana (Didi) Marie. We love strong classic feminine or neutral names that are well known and easy to spell but not especially popular today. Also having a cute nickname while they are young is desirable. Diana was an obvious pick.

Top first name contenders as of today: - Dorothy (Dottie) - Downside is everyone thinks of Oz - Matilda (Tilly) - Downside is everyone thinks of the movie and book.

Names that have been disqualified but that I like: - Emma (taken by a family member) - Catherine (don't want all royalty) - Elizabeth (don't want all royalty) - Harriet (wife vetoed) - Aurora (seems very recently popular) - Vivian (friend) - Lola (friend) - Scarlet friend) - Lilian (friend) - Tessa (relative) - Alice (friend) - Victoria (friend)

Potential middle names which are family names: - Jean - Joyce - Helen - Ryan - Rose

Would love any suggestions or feedback you all have. Thank you!