This isn't a terrible episode, it just feels sort of...empty. there's a universe in which we spend an entire episode on that initial planet, getting to know the side characters and watching them and the fam build up defenses together. There's a version of this episode in my mind that is actually about the aftermath of this massive war. What we get instead is an awful lot of meandering.

The story within a story here, with Brandon the guard, is the most interesting part of the episode, and most of that is due to intrigue. I can say I was very confused watching it for the first time, but I generally enjoy stories set in the past more than ones set in the future, so it's the part that really kept me watching.