This question seems less about themes and more about why people behave as they do. For instance,
• A fawning Mrs Bennet craves respect and admiration from a sycophantic society
• Elizabeth, with respect to Wickham, judges by cultured exterior alone
• A prudent Charlotte marries without love, for security in a hard world
• Mr Bennet keeps to himself, dismissing society's sham and glitz
• The cultivated Mr Darcy initially disdains the ill-behaved and uneducated lower classes
• Racy Wickham marries under duress, to avoid disgrace in a prudish society.