Currently admins can delete a page with all its edits, and also can undelete all or some of an article's deleted edits.
Often when history-merging I have had, as a preliminary, to temporarily delete late edits (often a bot edit) that had been added to the source after the cut-and-paste event, and to temporarily delete early edits (redirects and miscellaneous) that were at the destination's name before the cut-and-paste event which caused the need for the history-merge.
To do that, I must delete the file with all its edits, and then to undelete most of its edits. That wastes administrator time and internet time and Wikipedia server time. It would be easier if, when deleting a page, if I could select which of its edits to delete.
The history display of non-deleted edits already has a column of small square clickables, one per edit; this column could also be used to select edits to delete.
That column of clickables should have controls for "unmark all" and "invert the selection". (Selective undeleting already has an "invert the selection" feature.)