That'll help but most of your weight will come from the glass and resin over the balsa. Most of the torsional strength will also come from that too.

You may want to consider using nice light weight chosen 1/16 sheet for the sheeting. It would not weigh that much more and it'll be MUCH more resistant to finger pokes. Even with light glass cloth and resin on the outside the 1/32 sheet would still be prey to being ruptured inwards by errant finger pressure.

Use a scale and balsa density chart to chose 6 lb/cu ft or less for the 1/16 sheet and the weight of the extra thickness will be negligable.

It's quite a large model you're building and fairly heavy in the fuselage (not overly but still more or less average for a basic design) and so the overall weight of the model will be high enough that a reasonably firm grip on the wing will be required when moving it around. It would be a shame to rupture the sheeting for the sake of saving at most about 2 oz of balsa.