Learn English – Middle initial placement

I think it simply follows from the natural stress patterns of the English language. See here. Two syllable nouns generally have the stress on the first syllable. Many 3 syllable nouns also do. Words that depart from the natural stress patterns tend to be words borrowed from other languages, and there is a tendency for them to eventually get coerced into the native pattern if they are in the language long enough.

There might be something of interest to explore if female names are more likely to depart from that pattern--there may be a greater tendency to want to use foreign names or foreign pronunciations with female names, having to do with cultural notions of masculinity and feminimity (e.g. good Saxon words considered to sound manly, vs fancy French words).

In general, single quotation marks are only used to indicate a quote witihin a quote (at least in AmE).

In the case of a term that would call for quotation marks, such as a nickname, the single version would only be used if the nickname refernece was part of a quote. Also, in US practice, once a term is defined, such as a nickname, the quotes are usually omitted in subsequent references.