Her cost isn't so bad compared to Anya. Plus, like buttlover said, her skill will be pretty useful when you need an ATK boost to all units in your team.
With that said, mincosted her today with one skill level left. Guess I can casually farm for her now and hope I can gather up as many plat fairies as I can. Rolled Nadia recently and I'm planning on using her in the current subjugation. Though I'm not sure how good she is without her S.AW.