As a SM just starting a group of newbies to the game, a villian like Hetty is exatly what I'm looking ofr, without a doubt she'll be showing up at my table in a couple of weeks.
And while I may not agree with his choices about Hetty's charges, A small bit of personalization will clear that right up. THe grammer in the Tactics did bug me, I don;t really want to read that right before a combat, or during it for that matter.
Hetty is a perfect villian for a short horror campiagn, she even has offers of advancement, although I don't know how that fits in with the story, (a midwife assasin?) The fact that she can show up 4-5 levels after they have defeated her, and she can still cause the Pc's all sorts of grief is a wonderful way to provide and insure that the choices that Pc's make in one part of the game effect them latter, instead of a oneshot villian; they show up, fight, and Die. Heck, event he children she's raising could become Pc allies or antagonists depending on how this adventure goes.