It would be nice if you could have the ability to have different models for item damage variants inside the program instead of having to find out how to put them in the .json file manually. Did that make sense?
A bow has a durability of 384 therefor the model is, say "model A"
When you shoot the bow enough and the durability has gone down to 300 the model then changes to "model B"
You can keep shooting the bow and the durability will go down and the model will change with it.
This would be really helpful for people who make maps.