While SS was viewed the downfall of the anime by many, I really like the characterization and appearance of Nehellenia. She is very beautiful and actually have a personality unlike the other "big bads" of the anime series. Ambitious, ruthless, manipulative and extremely narcissistic.
I actually prefer the SS ending instead of the whitewash in Stars. The SS ending was very shocking, showing her being extremely crazy and narcissistic, rather to die or being sealed in the mirror and live as the old woman, that's different than the other big bads. The whitewashing was fine but unnecessary.