Appreciation and recognition of good contributors are important elements in Discourse. This is why (among other things) we have an option to show publicly that we like a post or a comment. Those hearts count and give users badges, trust levels, positions in rankings.
Wiki editors also deserve hearts, don’t they? Implementing this shouldn’t be a big deal? In the edit window the same UI element with the same behavior could be added next to the information of the edit.
Wiki edit hearts would count just as much as comments hearts.
Wiki editors would get the same notification than comment posters when receiving a “like”:
OK, if such “mini-post” would exist, then showing how many likes there would make sense. Still, I think my mockup would still stand for the action of giving thanks.
A sincere wiki “like” implies to check the diff, just as a sincere “like” in a thread implies reading the comment liked. Placing the like button next to the diff is equivalent to placing it next to the comment. Otherwise the UI would be encouraging blind hearts.
But anyway, as long as wiki edits can be liked with hearts that count, I don’t have strong opinions about the UI.