I hope I’m wrong, but I don’t think this will permanently resolve your issue with runtime.
Converting from user mode to a service isn’t actually related directly to being able to use snapshots or USN. I run Duplicati in user mode (non-service) on most of my machines but make sure they start elevated. As such I can utilize snapshots and USN. Also when you make this transition you can actually move/copy your database in order to save time (you don’t have to do the recreate procedure, although doing so is kind of a good test!)