Currently, when you create a model, you can't rename it. If you make a mistake or if your data model semantics change, you need to create a new model, port all your content to it, and delete the old one, which is impractical. Would be much better to be able to rename any model.
I would vote just just being able to change the label, or human friendly name, and expose the slug as a readonly change.
API consumers have to refer the to the model slug in their code, so being able to rename the slug could unexpectly break peoples code.