In MM ---> Mikitty, she just have the character to be a soloist instead of a group singer.
In Berryz ---> none, the members in BK is just nicely made to be as 1 group, I don't think they should be separated.
In C-ute ---> Maimi, she has that look of a soloist, even if she don't sing she still have the look to be a CM idol or something like that.