It's a thoughtful (and slightly extensive) analysis at Newsarama covering the fashion-sense of the first eight Doctors that sometimes dives into an analysis of the Doctors themselves.
Doctors 1 through 4:
http://www.newsarama.com/tv/agent-of-style-dr-who-1-4.html
Doctors 5 through 8:
http://www.newsarama.com/tv/agent-of-style-doctor-who-5-8.html
One of the interesting things brought up was that Tom Baker actually didn't like his costume in his final series. He essentially felt that at that point it had become more of a uniform and didn't allow for much variation--something that continued for the Fifth, Sixth, and Seventh Doctors (although the Seventh Doctor did change the color of his jacket in his final series to reflect the darker tone of his character).
The latter article also discusses offscreen evolutions of the costume of the Seventh and Eighth Doctors.
Doctors 1 through 4:
http://www.newsarama.com/tv/agent-of-style-dr-who-1-4.html
Doctors 5 through 8:
http://www.newsarama.com/tv/agent-of-style-doctor-who-5-8.html
One of the interesting things brought up was that Tom Baker actually didn't like his costume in his final series. He essentially felt that at that point it had become more of a uniform and didn't allow for much variation--something that continued for the Fifth, Sixth, and Seventh Doctors (although the Seventh Doctor did change the color of his jacket in his final series to reflect the darker tone of his character).
The latter article also discusses offscreen evolutions of the costume of the Seventh and Eighth Doctors.