Specify device for priority syncing
OneDrive should have a priority folder, probably giving the user the option to set on a specific device to which every other device will sync. This may eliminate the problem where you are syncing between two or more devices and you delete a file on one device but where the file exist on one another device which is not connected at the time it does not get deleted. When it does get connected, it is seen as a new file and uploads and suns to the other device and appears as the file you specifically deleted.
At least that is the reason I believe I keep getting unwanted files I deleted being downloaded continually.