What I am referring to is to do all I can to lighten up the plane during the construction stages, such as sanding the whole airframe a good bit where the wood is non-structural, like taking extra weight out of the nose block. Since the stab is solid, thick balsa, I have used lightening holes in the stab. Another technique that I have used is to put lightening holes down the bottom and sides in the long rung of planking. Sportsters tend to be tail heavy because the wood is all solid, as compared to more modern laser cut or skeletal designs. When I lightened up the airframe, don't use too much epoxy, a 60 tp 80 size engine is lighter than a heavier .90 and up size, and the performance is still solid with adequate vertical. Lighter wing loading naturally fly better and more agile and I find that little or no nose weight is needed to balance it.
Sorry I did not clarify my statement the first time. Good question.
Thanks for asking.