Yes, it would make it easier if he could freeze ahead. I don't think freezing makes anything sweeter & shouldn't make anything moister unless when thawing, condensation collects in the zip-lock.

My choice would be to freeze the cookie dough in logs unbaked & then bake when ready to go. Nothing beats freshly baked cookies. Most cakes can be frozen successfully depending on the icing if they're well-wrapped. Also, most cookie doughs will keep in the refrigerator for a while.

When i make cookies i put them in the frezzer. I got that from my mom and when we wented a cookie we would just put it in the microwave and thraw it that way.
Ilene