Vision of Lamashtu let's you send save or dies by dream. Aboleth's Lung is a pretty nasty one. For max cheese, you might even be able to apply a Geas which offers no save but has a long ass casting time, which is not a problem when you don't have to be on the same planet as the sleeping target.
Lipstitch blocks casting (and bite attacks, but as a fort save there's limited use for that) until the target takes a full round action to inflict damage to themselves, and even then suffer 20% spell failure and bleed till someone heals them. Here's the thing: It's a full round action to cut the thread, but they have to draw the weapon independently, taking another turn if they don't have quick draw (and given the nerf in PF, casters likely won't) or a weapon in-hand. That's two rounds before they can ever try casting spells with verbal components, and even then they take a 20% failure chance (Blindness/Deafness, by contrast, only gives a 20% failure rate, albeit at longer range).
Hag's Seasoning gives anyone who bites the target or ingests part of them temp HP equal to half your CL. Wouldn't be too interesting except the duration is permanent and there's no clause preventing the bag of cats trick from working on it. Cast it on livestock before slaughter and you can give a
lot of people some temp HP. Might even be able to preserve the meat and consume jerky for temp HP.
Arcane Malignancies is a bunch of Changeling only drawbacks you can get an extra trait with. In addition to some options to penalize skills you'd never use anyways, 55–57 is pretty good. You have to spend an hour cutting your hair every 48 hours or you get penalties when outdoors. You can actually squeeze some benefit out of this by having your character change her hairstyle every day, beyond what natural growth rate would allow.
Hag covens give a bunch of spells as at-will SLAs that take a full round action from each member to use. Iron Collar of the Unbound Coven lets a character with the Coven hex (which has a few ways to get it outside of Witch) remove the need for a hag to make a coven, and anyone else can use a Shawl of the Crone to join with only GP investment. Animate Dead, Control Weather, and Reincarnate are pretty powerful when stripped of their cost and casting times, and at will Speak with Dead is a GM's nightmare.
If you want stinky cheese, dominate or simulacrum a Winter Hag (CR7 Monstrous Humanoid, Will +8) for infinite simulacrums. A parasite familiar can do the domination at level 15 onward if you can knock out a Winter Hag first. A Serpentine Bloodline Sorcerer 9/Stargazer 1 can do everything needed for this cheese if they get friends to make a coven with.