Has any of the people that are in charge of producing each version of MediaWiki ever considered creating an extension that allows administrators to select revisions to delete through the page deletion system? This idea would obviously be different from Manual:RevisionDelete which deletes revisions through the revision deletion system, as opposed to the page deletion system.
I remember having this idea for years, and yet I can remember how surprised I was to find that there was no extension to my knowledge that allowed for revisions to be deleted through the page deletion system. Since there are specific sites that disallow pages in specific namespaces to be restored once deleted, unless the said users are in specific user-groups that aren't available to the general community.
The said extension would be pretty much identical to Manual:Page restoration only the exact opposite. As it would be added to the page deletion system and would allow for revisions to be deleted, instead of revisions to be restored.