well my vote is Persephone...I know little evidence to support it but for me its more of an elimination process...
Oracle? yes very strong and seemingly obvious candidate...which in my books, rules her out since W Bros clever to trick us. Is she originally to investigate human psyche then became the "fortune teller"? Is it not more likely she is designed for specific purpose of guiding the One back to the Source?
Trinity? might as well be Niobe (ie female characters).....I really can't see any strong points for this at all. The close link to Neo is all that goes to "support" this theory...
Persephone? well back to square one. Process of elimination is one. Another is programme to investigate "certain aspects of the human psyche," which can be taken as emotions, particularly love...hence her desire to experience his "real love" kiss. She asks the same of Niobe and Ghost so not just a "Neo thing"
also she is the "Mother of the Matrix" by her part in helping create the more "stable" form of Matrix today...she is NOT Neo or anyone else's mother literally
so don't freak out, its not an Oedipus complex thing
well, we'll all just have to wait till Nov