I should be able to create and download a text file: Needed for the Arisia Use Case, for the interim before we have a proper export API. We should be able to press a button and download the current jobs data.
In the Client, DataSetting.setThing() is deeply suspicious: It's side-effecty; worse, InputGadget.thingIdusually relies on it. It's a nasty code smell, and I've already encountered serious bugs caused by it. We should instead be rigorously setting data-thing explicitly when needed.
I can't recover from a Model Loop: If I manage to create a Model Loop -- a circular dependency -- there is no way to recover, because things crash too early.