Simplicity is a good objective, but there are limits.
An SOP to 'fly the aircraft' overlooks the need to adapt the 'standard' to the situation; do pilots have knowledge of the 'when and how to adapt'. These aspects can be primed with a good briefing by considering the differences between the expected situation and that trained for, particularly if training amalgamates GA with engine failure.
Many SOPs are written for the exceptional circumstance; GA, + engine fail, + max wt, + terrain limited. How many accidents have involved some or all of these aspects in combination, vs incidents during a normal GA. Many SOPs are not 'standard', they are abnormal procedures; a GA is just part of normal operation.
SOPs have to be written for the normal, we must train for the normal; brief for the abnormal. The industry needs to develop skills of awareness, planning ahead, knowing when and how to adapt, then review and learn from debriefing.
However there are significant obstacles to this in the training mantra, to always follow SOPs, which may adversely influence and restrict pilots' flexibility and adaptability in those situations when most needed.
Procedure writers need to review SOPs for ambiguity, unpublished assumptions, or specific situations where 'standard' does not apply.
Provide explanation and context; as indicated in #29 'moderate', 'tweak', 'as appropriate'; these also require knowledge of how and when.
... the best laid plans ..... frequently have to adapt to reality.
Things are 'simple' before thinking, but simplicity is only enabled after thought.