Sir Walter Elliot certainly thinks there is a connection between appearance and identity. His deep distresses are the little crows-feet line about Lady Russell's temples and Mary's coarse skin:
Mary coarse, every face in the neighbourhood worsting, and the rapid increase of the crow's foot about Lady Russell's temples had long been a distress to him.
On the other hand, his pride and slight delusion is that Elizabeth looks as youthful and lovely as ever and that he is still the handsome man whose looks beguiled the sensible and good Lady Elliot to become Lady Elliot:
Elizabeth, still the same handsome Miss Elliot that she had begun to be thirteen years ago, and Sir Walter might be excused, ... for thinking himself and Elizabeth as blooming as ever, ....
Lady Russell also adheres to the principle of the connection between appearances and identity but in a different fashion. To her, the appearance of financial stability and growing accumulation of wealth is the key indicator of identity. This is proved in her disapproval of Wentworth who--despite his real options for claiming a fortune off the spoils of a successfully fought war--was based on his appearance of present and continuing penury, or lack of wealth. The converse of this occurring when Wentworth returned from the war as a wealthy captain of his own ship exemplified her continuing adherence to the principle upholding the connection between appearance and identity.
Some characters, such as our heroine Anne and Mrs. Smith, who have higher characters and moral integrity, realize that appearance and identity may be disparate and seemingly contradictory components of a person's life. In fact, they see the ironic inverse of the principle. For instance, cousin William Elliot has the appearance of an noble identity yet is scheming for a connection with the family again in keeping with his ways, which Mrs. Smith calls "black and hollow at heart" since he is, as she says, a "designing, wary, cold-blooded being who thinks only of himself."
Returning to Sir Walter, his real situation in life again proves Anne's and Mrs. Smith's superior beliefs about the disparate and contradictory connection between appearance and identity. Sir Walter's identity is particularly ironic since he is baronet, which is an hereditary British title of honor bestowed on commoners and is the lowest of hereditary ranks. Baronet ranks just above the nonhereditary honor of knight and below baron. This in reality makes Sir Walter the lowest of the best not the best of the best as he likes to maintain the appearance of being.