TL;DR
Whenever I work through the Suggested Edits Review Queue, I find edits on questions that should be closed instead of bothering to edit them. I would like to have a new edit reject reason similar to this:
Post should be flagged
This question or answer is either off-topic or of low enough quality that it should be flagged for closure or deletion instead of being edited.
Note: I know this could be worded more succinctly, but I'm not much of a wordsmith. I'll leave that to the UI experts.
Details
This is sort of a follow-up to a previous request of mine: Add a "Reject and Flag Original Post" button to Suggested Edit Review Queue Interface. In that post, I suggested adding an option to reject an edit and flag the original post in with one button. I agree with Shog9's response to that request, which is essentially, "Reviewing edits is hard enough. We want reviewers to focus on the edit rather than the original post, and we don't really need another button cluttering up the interface". His suggestion was to reject edits with the "No improvement whatsoever" reason, then go flag the original post.
I have used that suggestion for a while now, and while it works for individual posts, it does nothing to prevent future edits to close-worthy posts. I would like a standard way to say to the editor, "Stop wasting your time and the time of reviewers on something that should just be closed." I agree that suggested edit reviewers should focus on the edits rather than the original post, but sometimes edits are on questions that are so unambiguously off-topic or terrible, that I can't help but see that it should be closed. I would like a more clear way to communicate that to them.
I think this would actually be helpful to new Stack Exchange users that make edits that really do clean up formatting, grammar, and spelling, but do it on posts that they don't realize should just be closed. If I were a new user and saw the reject reason of "No improvement whatsoever" when the post is clearly better formatted after my work, I would be confused and annoyed.
Examples
https://stackoverflow.com/review/suggested-edits/8263364
https://stackoverflow.com/review/suggested-edits/8730521
https://stackoverflow.com/review/suggested-edits/8374080
https://stackoverflow.com/review/suggested-edits/7067805
https://stackoverflow.com/review/suggested-edits/6997529