I believe reworking New/Inbox is deeply coupled with how to add an Ignored/Skipped state. I tried making sketches of what I see as problematic with the current state transitions, how I suggest them to be fixed and how the existing GitHub ticket suggests them to be fixed. Please see the post I just made containing them.
So yes, I am suggesting to be able to add items to the Inbox. Essentially because it makes sense to do so. The only reason for not allowing it is because the current implementation of auto-download has problems with it. Are there other reasons for preventing a simple model for episode state transitions?