Right, so I think we need to decide what's best for the short-term, and then also create a story to capture the long-term requirements.

The main tradeoff for the short-term seems to be between these 2:

1. keeping queues around (as-is in this PR) which could cause a conflict if a new stream with the same name is created, and which also puts a cleanup burden on the user rather than being automatic
2. losing-in-transit-messages (with auto-delete)

Thoughts?