Presence of body and mind on the act of flying is one hundred percent when flying in real life. The same is not true in case of simming. This is compounded by limited field of vision and gaming grade hardware.
I have seen that making a conscious effort of not moving my gaze from the end of runway and focussing my mind and body on maintaining centerline with anticipation and quick and small corrective actions actually improved my takeoffs.
Setting the power requies a few gazes off the runway. If this can be reduced by pre-determining the physical throttle position for the appropriate power setting, the gaze could then be fixed on the runway end.