Usually you don't want to move your hands a lot, else you'd be fine with a non-split keyboard.

But then there's very little room to put a pointer control device. With the bulky mechanical switches, you have virtually no room to squeeze in a trackpoint, like on laptops. Also, you want the space comfortably reachable by thumbs for keys.

And if you agree to lift and move your hand anyway, why not use a mouse of your choosing?

I don't yet have a solution.