In our organization it would be handy if an issue could be editable only for a selected group of members. E.g. for a team, or only for maintainers. By editing I mean others could not modity the description and the title of the issue, could not tick checkboxes, change the properties (label, assignee, milestone, project), but I would like to keep the commenting possibility for them.
As far I know, the currently existing locking conversation results quite the contrary.