I've used Blizzard Princess in a few decks, mostly Charmer-related ones. She is pretty good as a beatstick, and she becomes a whopping 3600 if equipped with Bound Wand. I don't recommend her for Unpossessed builds, though. Not enough synergy.
My current Charmer deck irl uses 1 Blizzard Princess, 1 Ice Queen, and 1 Sorciere de Fleur.