As a user, I would like to be able to automatically back up my DB graph from the desktop app in case something happens to my local hard drive. I don't need to access the graph from multiple devices, I just don't want to lose data if my PC hard drive dies.
I don't see a way to change the default file system location used to store the graph, and even if I did I'm not sure that storing an SQL Lite database that is being actively worked on in OneDrive or other cloud storage provider is a good idea.