The Pencil makes it even harder to use in some cases. I would never type on an external keyboard, move my hand to pick up a pencil to reach up to the screen at an awkward angle with no hand support to make an edit then put it back down, and move my hand back to the keyboard, that's so many more steps than just moving my thumb to a trackpad, or to the side of the keyboard. Besides, Apple tells us that lifting one's hand to touch a screen makes no sense on a laptop because it's fatiguing and ergonomically inefficient. And I'd hate to place my Pencil on the iPad, and have to reach for, and pull it off its magnets every time I wanted to edit some aspect fo a document, then put it back, or risk it getting lost in the sheets or the couch cushions. But that's just me.
So don't assume what works for you, however inexplicably, works for everyone, including Apple. I can't even fathom how you'd juggle all of those items and a keyboard, per the OP, comfortably while laying back on a sofa, much less a bed.