While Iron Helga is better than Olaf, plenty of other names would serve better. I also suggest Jasmine Sage as an alternative name to Karthus.
[Karthus] Kess Eventide
[Karthus] Shayd
Lilli (No change)
[Lilli] Dread Violet
[Lilli] Scarletta Blayd
Iron Helga (No change)
Shiverin
Valla Steele
While Iron Helga is better than Olaf, plenty of other names would serve better. I also suggest Jasmine Sage as an alternative name to Karthus.