Spock. He's a wonderful straight man, with just the right amount of occasional jerkass commentary regarding humans (like at the end of Mirror, Mirror
). He was always my favorite, and after watching a bit more of TOS at its highs, he still is.
Picard actually is my favorite, I think. He has both sophistication and badass-ness, and he'll always be special to me as being the most cerebral captain.
A favorite...hm. Probably a four-way tie among Ezri, Garak, O'Brien, and Sisko. So it kinda counts since Sisko is in the tie? I really do love all of DS9's mains, and it's hard to narrow it down to even 4.
Favorite is the doctor. Janeway was too ridiculously inconsistent to like on anything more than an episode-to-episode basis.
Travis, I suppose, but that's more of a case of "who do I dislike the least?" more than who I like the most.