Which is not an acceptable greeting for strangers of the opposite sex?

• Personal endearments like Honey, Darling, Sugar & Sweetheart are entirely appropriate usage down south.  
• "Y'all", while somewhat remote and aloof, is universally acceptable, particularly if appended with complimentary or instructive comments, like "Y'all looking good", or "Y'all come on in and get cool."
• Hey = 8  points.  This is considered rude and will probably elicit a recitation of that old saying - "Hay is for horses, not folks."