Positive

• 'his air was grave and stately, and his manners were very formal'

  he's polite, well mannered; this makes him the perfect husband for either one of the Bennet sisters or Charlotte Lucas
• 'perhaps, when we are better acquainted-'

  'He's maintaining the contact by assuming that they will become closer over time. This makes him a bit ambitious, which some would view as positive
• 'He begged pardon for having displeased her'

  Could be geniune and well mannered, or he could be pretentious and only presenting a facade of a polite person
• 'I have frequently wished to heal the breach'

  Presenting his bevenolence