Two points of feedback:
1. Can y'all provide concrete examples of how you would find RETURNING
useful. I can imagine cases where it would be useful, but in my own
database programming (which this days is mostly confined to working
on the [Fossil][1] source code) I don't
recall ever coming across any such cases.
2. Anyone who is seriously interested in encouraging the implementation
of new features through funding is welcomed to contact me directly
at "drh at sqlite dot org".
[1]: https://fossil-scm.org/fossil