Sisko, who lost his wife, raises a son alone, becomes a reluctant religious icon, and has a unique connection with an unusual alien race, the Prophets... not interesting? Kira, who had to help defend her planet from a repressive race since she was a child, also serving under a superior officer who is a religious icon to her, also having to come to terms with her terrorist activities as well as trying to see not alk Cardassians are evil... not interesting? Dax, who has lived 8 previous lifetimes, one of whom was a mentor to Sisko, not interesting? Odo, who is a shapeshifter, had no idea where he came from, and he eventually finds out only to discover they are rulers of a totalitarian empire, and caught between his sense of justice and desire to luve with his people, not interesting? Quark, Bashir, O'Brien, Jake... not interesting? (This post would become excessively long if I wrote more.) From the jump, DS9 had the most interesting characters, and the most real ones.