@Manbearcat - a rules set you may want to have a gander at is Vagabonds of Dyfed. It's an OSR-adjacent fantasy rules set that uses a lot of PbtA and FitD bits to make it run. It's somewhat the opposite of your idea in that it's more PbtA with some Blades stuff mixed in, but the fusion might still be useful, as might the approach to the fantasy elements there. which is a little more S&S than DW is and grants the game a very different feel. It's also interesting in that it's classless and runs on abilities chosen from a master list, so there might be some stuff you can punk and adapt for the playbooks you want to design.