I’m in the process of developing a library of useful, reusable components that could be dropped as an external library into a SpriteKit project.
They include things like my NodeComponent and an abstracted way of managing three different kinds of input from either macOS or iOS (single tap/left click, double tap/right click, and pan/mouse drag). It also has a physics component and a render component—things that come up in games of all different types.
The components often have a lot of editable properties that affect how entities behave in the game. Tagging these properties with the @GKInspectable tag allows you to use these components within the SpriteKit visual editor.