This is so cool!
Interesting how a creative process evolves
Thank you. It is a at time rewarding process and at others frustrating beyond belief.
... Air circulation?
Breyers are hollow like ponies and made of cellulose acetate which is derived from an organic compound. They suffer breakdown problems like ponies do. Some think a small hole in the plastic keeps moisture from building up in them and keeps them from breaking down faster. Breyers typically have a small hole in a nostril.
This. I've also seen models that bloat and warp without that hole. so sad.
Actaully for the most part they are much hardier then ponies, yes there are certain ones who end up as bloaties or shrinkies but way less issues then ponies.
You do need air holes especially with customs since you are putting on materials that do not "breath" at the same rate.