First off, this is a cool idea that seems useful…until I remembered that every dashboard I’ve personally deployed from this source I have also modified. Some have only been adjusted in very small ways, such as to accommodate quirks in my data source, etc, but all of them have been modded.
With that in mind, I don’t see a way to problematically import and deploy new versions without messing up people’s existing deployments.
I did have the thought that you could download the JSON for the new version and compare it to what you are using in your current version to look for changes/updates you might want to incorporate. This is not automatic, but is more likely to work.