I want to create an easy to use game engine for iPads and maybe iPhones, and I feel like using Apple's APIs would be the best toolset for this job. With that said, would it make more sense to use their high level frameworks like SpriteKit or SceneKit for this, or should I use their low level Metal framework?

The benefits of SpriteKit and SceneKit is that all the rendering code is done already, all the input handling, physics, particles, etc, and it would make this engine much faster to develop. But, if I use Metal, it would give me more control over what to render. The question now is, do I really need low level rendering for this specific project? Should I care about the amount of control offered to the users of this engine? Or is this a question I have to answer myself?

This would be my first attempt at a game engine, but I've got ~2 years of programming experience with other game engines like Unity, and I've dabbled in Swift for iOS apps.