You know, I’m kind of just spitballing, but if you wanted to go beyond “this balances group shots/group songs,” Chibs could slot into the outer team pretty well, not just because she has two (2) friends and they are both there, but because they all kind of have the common thread of not quite being the senshi they should be. There isn’t supposed to be an outers team at all, Saturn is supposed to exist briefly to be the world’s panic button and Pluto is supposed to primarily guard the time door, and while we’re less clear on Uranus and Neptune, I think at best they’re supposed to team up for big missions and otherwise patrol for threats alone. But this isn’t the Silver Millennium and they’ve carved a new path.
And Chibs, I feel, is supposed to be another Serenity but despite the name she’s too much her own person. She’s pragmatic and cynical at times and she’ll never be the chosen child of the Crystal the way her mother is.
And pair that with the fact that, like the outers, she’s often been dealt the harder hands, I think she’d be drawn to work with them