@Preston_Bannister yeah, you’re absolutely right about the variation. I found a pretty big range when I was googling values. For what looked like representative middling numbers, the axial (along grain) strength of balsa was similar to plastic, but the across-grain tensile strength of any wood is very poor, and balsa is a relatively weak wood. So it’s going to greatly depend on load orientation relative to grain for the balsa, while plastic is relatively isotropic in comparison.
@Ryan_Carlyle OK, that makes sense. The entire reason flying models have complex structure (and fabrication) is to place load along the grain. Practically, there is no load across the grain.
So my unsupported subjective opinion has a chance. 