Champions are Seras that have a Cause and morals that they stick to and go out of their way to make other's lives better. Vampire Slayer Sera is probably the best example. Maybe Rey too. Don't like killing people and will go out of their way to avoid it.

Wanderer Seras are... they have no native morals apart from "Not Terri-aunt's". They can easily shift into another cluster. They tend to be kind of listless and not a lot of drive to Do Things that aren't just survival. Will kill people, but only if they attack her first.

Exile Seras are are sort of Stage Two Cluster? They were either a Wanderer or a Champion cluster and moved into the Exile after Big Shit went down. Mostly trauma. They're more sadistic than normal. How zero qualms about killing.