Favorite would be really hard to say. “The Trouble with Tribbles” and “A Piece of the Action” are a lot of fun, as far as comedy goes. “City on the Edge of Forever” is hard to beat on the more dramatic end. Honestly, there are too many good ones to list.
Least favorite is either “The Paradise Syndrome” or “Turnabout Intruder”. The former is impossible to enjoy even in a “so bad it’s good” way, what with Kirk thinking he’s some kind of space Native American. But the worst part is that he’s down there for
months. He gets married, his wife gets pregnant, but both wife and child end up dead, and this doesn’t affect him at all. I mean, I know he’s had a lot of love interests, but you’d think watching your wife die would merit some kind of reaction. Nope. He remembers that he’s actually not a Native America from space, and that’s pretty much it.
“Turnabout Intruder” doesn’t make any sense, and the moral appears to be “women can’t be captains because they’re too emotional”. :ehh: