What’s your favorite TYPE of Star Trek episode?
Tribbles
Think about it, Tribble episodes have aliens of the week, Klingons, time travel and character development. I would have loved an episode where the Tribbles wind up on the Borg Cube.
Character development, first and foremost, but I’m not averse to a mysterious passenger, a space battle or a spatial anomaly (as long as it’s original, and isn’t fixed in the last five minutes by some unconvincing Treknobabble).
Something else - moral dilemmas.
I like the DS9 episodes where Sisko had to decide on his part in the wars that he helped to continue.
I like the episode where Picard had to decide (with the help of Q) whether he wanted to go back in time to undo the action that led to his needing a new heart. It turned out he would have been a very different person.
I like the defection storylines where people have to decide between a moral stance and leaving their loved ones behind.