OK, now that I've made at least the attempt to improve And the Children Shall Lead, what have I learned from the attempt. I would slightly revise what I said before. Before I said that And the Children Shall Lead had only one plot, the Gorgan taking over the Enterprise, but there are two angles on the plot, either one promising but not possible to do both right at the same time. But actually there is one plot with three angles. The plot is the Gorgan taking over the Enterprise. One angle is the creepy-legend-that-comes-true angle (and all the mystery of what his happening). The second is the villain-manipulating-children-against-their-parents angle. And there is the if-you-face-your-deepest-fear-you-will-overcome-it angle.
None of these angles is very original, but so what? As my grandfather used to say, unlike cliches, themes never wear out. Any one of these themes/angles, done right, could make a good story. Maybe a two to two and a half hour movie could do justice to all three themes. A one hour TV show cannot. I would say that to do any one theme justice, you would have to demote the other theme to secondary and exclude the third theme altogether. One of these three angles cannot be removed. That is the Gorgan manipulating the children against their parents. Since the episode is entitled And the Children Shall Lead, and since its absolutely central premise is the evil being and its child followers, any reasonable version of the episode would have to give us some insight into how the Gorgan turns the children so far against their parents that they don't even care if they are lying dead all around. Either the legend or the beast can be left out. One of the two should be left out. And of the two surviving angles one (either) should be subordinated to make room for the other to be fully developed.
Clearly my version focuses primarily on the creepy legend and how it comes true. I flesh the legend out and then use it to explain what this mysterious being is and what it wants. Secondarily, I show the evil being manipulating the children and turning them against, not just their parents, but all adults. I do not claim to do this part very well. A whole lot more complex psychology would be needed to make this part convincing. And I leave out the overcoming your fears angle altogether. That makes the children's mind control seem very generic and denies our hero the chance to overcome it by sheer force of will. But it removes a bunch of vapid, mindless platitudes, so I still consider it an improvement.
There are other ways to modify this episode. One might focus on the psychology of how the Gorgan manipulates the children and reduce the legend to a secondary role. Or one might leave the legend out altogether and focus either primarily on the Gorgan manipulating the children, or on the children manipulating the crew by invoking their fears and Captain Kirk overcoming his. Although I think that even if you omit the legend, you need some kind of explanation of what the Gorgan is, and a better one than actual episode offered. I do not claim that my approach is the best. Arguably, it is the worst approach because it sacrifices psychology to legend and explanation and omits the more profound potential of the episode. I can only plead that I am just not a good enough writer (especially a psychological writer) to do the other approaches justice.
But, I flatter myself, despite the overly long and talky briefing room scene, it is an improvement on the original.