My experience with mouse-activated featrures in FSX is that it takes too much time lining up the cursor with the control and activating it. A real pilot knew where the controls and switches were by memory and could activate them by feel using both hands without having to look, or at least with only peripheral vision.
If you speed up the mouse movement, you inevitably overshoot the control and spend a lot of time backtracking. This might be an interesting scenario for a full-real start of a bomber using complex engine management - once. After that - trust me - you will be back to the keyboard
