In its general storytelling style, Trek had plenty in common with the many and varied Westerns that populated the TV landscape in that era. It doesn't particularly resemble Wagon Train from what I've seen of that show, however...WT was much more of a semi-anthology, with stronger focus on guest characters of the week and their stories than on the recurring cast.
Indeed, very guest-star driven; almost all of the episode titles are in the format of "The [insert guest character name] Story." They sometimes had "name" guests, movie actors past the prime of their careers. The one I watched last night had Lou Costello as a well-meaning drunk who travels with an orphan girl and "stows away" in the wagon company. (The girl was played by Beverly Washburn who was a victim of "The Deadly Years.") The other day it was William Bendix, and a couple with Marjorie Main before that.
What was similar to ST was that the premise involved constant travel, so the core of regulars could be in completely different settings with different guests every week.
Rawhide did this, too.
Cheyenne,
Have Gun Will Travel and
Wanted Dead or Alive also traveled all over the West, but their stars were pretty much solo.
Anyone ever read about James Garner and his TV series Maverick with the revolving cast?
That wasn't a creative decision, it was mainly to do with inexperience making a weekly full-hour show; they got behind in production so they brought in Jack Kelly as a second lead who could be shooting another episode with a different crew at the same time as the one with Garner. The scripts could star Garner or Kelly interchangeably, they weren't written specifically for the characters except when Bret and Bart were both in the whole episode. This caused some real problems with sponsors who had bought the show with Garner as the star of every episode. To help alleviate some of the trouble this caused, Garner would shoot some short intros setting up Bart's adventure, or a short scene with Kelly for the very end, usually meeting up on a nondescript piece of trail.
The Name of the Game later used rotating leads, but it was 90 minutes and used extensive -- and expensive -- location shooting.
The Bold Ones, too, though that was more like three different series under one umbrella title. It's an interesting idea, that a show like
Star Trek would try something like that, perhaps to make time for effects work, but it was never considered that I've ever heard.
