Good question Rob, good subject.
These are related questions:
Have you actually weighted the stab and the corresponding pieces you are considering to replace the kit stab with for comparison?
Have you determined/considered the weight saved by cutting additional holes drilled in the kit stab ?
Have you determined/considered how the plane will balance after installing the RC and Electric components ?
Generally, the kit stab is light weight to begin with.
Probably more benefit can be gained by sanding a slight symmetrical airfoil shape to the kit stab. Use a Perma-A Grit sander, they are much faster than paper, etc.. The source link is on my web's "Links" page.
Sky Bench ... Woodys Forever