My new A16 iPad seems to use more power sitting closed much than I would have thought. I came here to say this, but found you got to it first. I hope someone here has some thoughts on the matter.

I am more Android guy, so I am not yet familiar with the options. Does the iPad have a power usage app describing what apps/services are using the power? Bluetooth for one to keep the Apple Pencil ready, I suppose.

yes, search for battery