Some things have changed since I first posted this, but, I think (in addition to some of the behind-the-scenes stuff you discuss), the biggest improvement would come from splitting “Something Else” into “Something Else Problematic” and “Something Else (Message Staff Privately)”.
The former would go into the review queue; the second into moderator messages. The message option could even be moved to the top, near “message the poster directly”…
This is because (as I think I said somewhere up in the OP), I want to encourage people to flag posts that need curation or other attention.