Ellynne,
Dayna - I'll normally agree 20, although I may yet put together a story in which she's Lauren's younger half-sister and lies about her age and place of birth because she knows how Federation humans feel about racial purity, which would make her younger (and, in which case, Hal Melanby's older daughter died on Earth but under circumstances where he can still pass of Dayna as her older sister, a protection if he ever encounters Federation personnel).
I always felt that the Federation had got to the stage of believing that racial and sexual discrimination were things of the distant past. Servalan detested Mellanby for political reasons, not because he was black. Also, Servalan's enemies never said that they detested her because she was a woman.
Murray