I think you might appreciate this talk, which uses a micro kernel to do a lot of the ideas you’re talking about.

https://www.usenix.org/conference/osdi14/technical-sessions/...

This could even allow resetting the state of the computer back in time so you can pick up exactly where you left off, or undo away mistakes regardless of app, etc.

Definitely some privacy concerns but for a self ran open source thing I think it could be really cool