Robert
No It wouldn't do much for cost and it wouldn't do much for performance either.
Good Performance is achieved by making sure the design utalizes proper wing loading. not excess power, Assumeing however that power is adequate, more of it only makes you use the throttle control stick more. Current engines have plenty of power. to fly a properly designed two meter pattern plane.
And until the size changes larger engines are not required.
I know some FAI pilots who have had to add weight to get their very light airplanes to fly properly. You see the very light or heavy really don't count but the proper weight does.