I think Galaxia is more likely paralleled to Akio. Who once was a hero but went corrupted by the "adults' world".
Neither of it was handled well. Chaos Galaxia was too evil that she killed all other senshi. Usagi should have defeated her THEN redeem her. There was NO plot to let the audience feel relieved after she had killed all the senshi.
Akio should have been shocked by Utena's action that she was able to use the power he had long lost, finding his good heart back, then sacrificed himself to save himself to save the world. I feel that he was made into more of a symbol than a human being.