I have a theory, the current doctor when you started watching is your favorite doctor. Would this apply to you?
I started watching Dr who when the reboot was 3 seasons in, I think David Tennant was the greatest doctor. A few years later I finally got wife to give it a shot as I started a fresh rewatch in preparation for Matt Smith's second season, she was ok with Eccelston and Tennant but Matt Smith is far and away her favorite doctor. Does this pattern hold true for any other Dr fans?
When I started watching it was on PBS in the United States in the 1980s, and they showed the Doctors in mixed-up order. The Doctor who first caught my eye was Tom Baker, the most popular by far among US viewers and also the one most likely to turn up in the reruns simply because they were rebroadcasting (mostly) stuff from the color era; I loved the grinning madman with jellybabies and scarf with the blasts of Douglas Adams humor. However, when I grew to have a truly favorite Doctor I realized I was a Colin Baker fan and still am.