Technically the heaviest gauge spokes your hubs/rims can take will be the stiffest but often times there is a point where you just don't need stiffer. I built a set of 3x 32h wheels with 14/15/14 spokes for Danny Robertson and he claimed they were as stiff as his discs and he was at one point one of the strongest US sprinters out there. Those were on pretty standard Dura Ace hubs and an Origin 8 rim with a similar profile to Deep V's. So yes, technically you can chase the theoretical stiffest spoke out there but there is a point where you are just adding weight and not any noticeable improvement in stiffness.