Rainboe, you write;
Guarding the speedbrake handle is no good, you unfortunately need both hands, one on the controls, and one to keep free for the MSP and throttles.
Why do you need to touch the throttles when the speedbrake is extended?
Other than aligning the HDG bug very occaisionally, why do you need to touch the MSP? All the other inputs can be made by your oppo in the seat next to you.