One thing you can do to make this use-case work better is to combine the spreadsheet as API with a static site generator.
I made this very basic plugin for Jekyll:
https://github.com/netlify/jekyll-gdrive
That'll let you use a Google spreadsheet as a datasource and expose the data to your liquid templates.
Combine it with something like https://www.netlify.com that'll run the builds for you and let you trigger builds via webhooks, and you have a Google spreadsheet based publishing engine where the final sites are completely static and live straight on a CDN.
Used it for one site where we used the scripting options of Google spreadsheets to add a "Publish Now" image button to the sheet, so in the end user could edit the the sheet, and then press "Publish" to trigger a build+deploy.
If the users are already used to spredsheets, it can be a really handy little anti CMS :)
[disclaimer: I'm a founder of netlify]