I'd like to be able to both add and edit templates. But if SE isn't ready to give us the ability to add new templates yet (which has some design implications), could we please at least have the ability to edit the existing ones?
On one of the sites I moderate we've had a recurring problem with rudeness, and we have a meta post that supplements the "Be Nice" help topic. Ideally we would link to that meta post in our mod messages about rudeness, but often I don't because I have to go find the post and manually insert it each time and sometimes, err, you need to send these messages out in batches. It would help me and my fellow mods a lot if we could make that edit to the template on our site.
It would be best for the revision history to be available (like on other posts and help topics), as a check against too much unintentional drift from the original point of the message. It could be editable by a single moderator, like certain pages in the help center, or require a second to concur, like custom off-topic reasons and redactions -- either would be fine.