I've tackled the problem so many times and had so many different solutions depending on the client.
Instead of providing a stupid and bloated CMS to do things I don't want it to do and let the user break things that they shouldn't be breaking, there's this.
I could possibly just provide them with access to edit some markdown with a link or two and instructions on how to make the edits. It puts a bit more burden on the user, but it also means they don't have to pay to run or setup a dynamic and crazy CMS platform too.
If someone could productize this as a service, provide a pretty interface for it, and let it be an easy CMSaaS that gives me, the developer, lots of options and access, but provides a dead simple and easy editor that I could give to my clients, I think that'd be great.