I liked Payne's point about the vulnerability of Sparks with just enough to be identified and limited education/resources; there's only so much they can do, but it's enough to make new and exciting forms of trouble. Presumably some of them still turn it to advantage at home, but then Payne spends all his time with the ones who survived and ran away....

Tangentially, a friend of mine suggested that in that universe, some fairytale stuff might reflect what Sparks were doing at past levels of technology. A coverlet of bells that could be heard across nine kingdoms is totally something a Spark would come up with.