The best medium is the one that allows for the widest range of storytelling styles, from big sprawling epic to quiet "day in the life of a minor character". TV, comics, and novels seem well suited for this, whereas movies tends to force things into the big bombastic epic category. When one looks at the list of the best Star Trek episodes and novels, it becomes clear that best Star Trek stories would generally make for pretty boring movies. That should make it pretty clear that the movies is not the best place for Star Trek.
I'm not even going to count video games, because too much depends on the competence of the player, the user-friendliness of the interface, and they all tend to boil down to "blow up the other ship" type of thing anyway.
I'm not even going to count video games, because too much depends on the competence of the player, the user-friendliness of the interface, and they all tend to boil down to "blow up the other ship" type of thing anyway.