How would you describe Alexandra in To Kill a Mockingbird?

Aunt Alexandra is the sister of Atticus and Jack.  She is married to Jimmy, who rarely speaks or works.  They live at Finch's Landing.  They have an adult son, Henry.  He is married and has his own son, Francis.  Aunt Alexandra coddles Francis.  She teaches him how to cook and tells him her opinion on many things.  She is a good cook, and every year she prepares a large Christmas meal.

Family heritage and Maycomb County are important to Aunt Alexandra.  She is proud to be a Finch.  She thinks that Scout needs to act more like a young lady, and one of the reasons is so that she can help maintain the Finch image around town.  Aunt Alexandra is very proper, and she believes in dressing appropriately.  In Chapter 13, Scout describes her aunt's outward appearance:

She was not fat, but solid, and she chose protective garments that drew up her bosom to giddy heights, pinched in her waist, flared out her rear, and managed to suggest that Aunt Alexandra's was once an hour-glass figure. From any angle, it was formidable.

Atticus and Uncle Jack are warm and friendly.  They are usually easy-going and kind.  Aunt Alexandra does not naturally share these traits.  Scout sees her aunt as an oddity in the family:

... I decided that she had been swapped at birth, that my grandparents had perhaps received a Crawford instead of a Finch.  Had I ever harbored the mystical notions about mountains that seem to obsess lawyers and judges, Aunt Alexandra would have been analogous to Mount Everest: throughout my early life, she was cold and there (To Kill a Mockingbird, Chapter 9).

When Aunt Alexandra moves into the Finch house, she becomes involved with the missionary circle.  She is an excellent hostess, hosting teas in the Finch home.  Scout also describes her aunt's manners and demeanor:

... she had river-boat, boarding-school manners; let any moral come along and she would uphold it; she was born in the objective case; she was an incurable gossip.  When Aunt Alexandra went to school, self-doubt could not be found in any textbook, so she knew not its meaning.  She was never bored, and given the slightest chance she would exercise her royal prerogative: she would arrange, advise, caution, and warn.