There's one or two aspects of Winter that you missed that imo are important enough to mention. For one, Winter can be distracted. In fact, we've done so as much as humanly possible by taking max Harshness dice so Winter has a relatively light touch on our neighbors.
Winter doesn't actually want the people of Union wiped out, although the latter assumption is pretty reasonable in-universe. Following the anthill analogy, Winter doesn't mind frying some ants, but doesn't want the entire anthill wiped out. That would ruin their fun. Good thing too, otherwise we'd all be dead.
I found that option gets a whole lot more appealing when viewed from a different perspective. Don't look at it as an outright replacement for Sara and the Silent Blades. Look at it as a way to keep the Devourers from taking advantage of our other Vermin-killing actions while simultaneously softening them up for when we go all "Army of Darkness" on the suckers. It probably wouldn't even delay the eventual completion, since we'd need to kill those suckers during the attrition phase anyways. As such, we could use it to remove either the Silent Blades and Sara, or the Warrior's Son+Skirmishers off of Vermin-killing.
We could use the Silent Blades on Razorweed (I suspect that Sara's supervision should keep accidents from happening) or Deadport. We might even be able to split the dice should we have an action in the area that would allow for minimal scrutiny by the living, like that underground animal shelter (although personally I'm hoping that our new rituals will allow us to house them in our well defended houses).
More interesting are the possibilities offered by removing the Son+Skirmishers. We have quite a few actions going in their area of expertise, so freeing up those dice would be valuable indeed, even without factoring in the additional bonuses.
Alternatively, we could take neither off of [Away with the Pests], instead transferring them to other targets. One small shuffle could have the Blades handle the Eyevines while the Skirmishers handle the Woodflesh Spiders, since we could probably manage to purge all of the latter in a single turn. Another option, and I wouldn't be suggesting this if it wasn't for Bound's combat boost, is to leave the Son and co. where they are and send Sara after one of the Lords. Between the aforementioned boost, synergies, and omake bonuses, I think doing so would be fairly safe. The benefits of such an action for when Winter hits and beyond practically go without saying.
Out of curiosity would "others" include Scholomance graduates?
