I feel like Baby was little kid's favourite. She was my favourite as a kid. But as a kid, Scary seemed like the main one. But now that I'm older, and I've seen documentaries on them, I can recognise that it was actually Ginger/Geri.
It depended on the song tbh but Mel C and B were starting to take lead as time went on.
Mel C and Emma pretty much ruled Too Much. Emma was the only one who could do the chorus.