Exploring how to spawn pieces
I recorded a short stream about adding the first pieces and having them fall. You can see it here: https://www.youtube.com/watch?v=HdxNykxT0Os
The idea is to have a SpriteKit scene (.sks) file and design the pieces inside there. Then load the scene, and use the predesign nodes as templates.
I don't yet know how to duplicate nodes, but loading the scene and spawning pieces worked out fine.
Here's a sneak-peak of my Procreate skills, and the end-result: