Stargate Atlantis is a stupid scifi show. It’s about some action heroes and scientists from Earth who are off in another galaxy fighting space vampires. Everywhere they go, people speak English. Every episode is a fantastic adventure, usually involving space battles and/or noble savages on the planet of the week. Everybody almost dies all the time.
Battlestar Galactica is a clever scifi show. It’s a grim portrayal of the survivors of a nuclear holocaust, who are fleeing robots with the ability to look like humans. It has well-developed characters who are allowed to progress throughout the series. There are no aliens, no natives, just battle-hardened space-soldiers colliding in cramped quarters.
Stargate Atlantis is smart. It plays with its conventions in unexpected ways, capturing your interest even though you know what they’re doing. There are silly stories, but they end after 43 minutes, doing no lasting damage to the better stories that follow. It’s Star Trek, but it’s good Star Trek, and even Star Trek was rarely that. It’s fun.
Battlestar Galactica is idiotic. It has gradually built a story arc of monumental idiocy, involving the worst of fantasy cliches: The Five this, and The One that, and some mystical author-force that steps in whenever the yarn-spinners want something Awesome to happen. It’s one big silly story, maintaining interest only by promising shocking Revelations down the line. And they’re forced to stick with their silly choices, because that’s what a serious and arc-based show does.
Lesson: Everybody you’ve recommended Galactica to now hates you.