A recent trend seems to be delete voting a question immediately after it's closed. While I like the sentiment, it has caused issues. Quite often, the question will be deleted within minutes of asking. So quick that the original poster never sees that it was closed and just sees it disappear. So they think there was a bug and re-post the same question. This obviously is not great for several reasons. Here is a question that it almost happened to today (2 delete votes within 3 minutes of asking)...
I propose a "Delete Window". Basically, we'd still allow delete votes immediately after close. However once the necessary number of votes is received, a banner will appear on the question saying "This question is marked for deletion". Then it will remain available for some fixed time window as read-only (perhaps 1 hour). That way the poster can have time to see the fact that it was closed (and the marked duplicates).
The existence of the 20k 'rapid delete' has added some spice to this problem. A user submits a really poor question -- beyond reasonable repair. Within moments, it's both closed and deleted. Well, this is fine, except that it lacks a feedback path to the user, unless that user was watching closely enough to see the comments and/or close reason before the delete happened.