I think it would be worthwhile to look into eliminating the USB syncing service and moving to a model where configs, roms, saves, logs etc are all stored on a USB storage device and the “system” is kept to the SD card.
-Minimize writes to the SD card, thereby minimizing wear & potential for corruption during a power dip or failure
-Allow for optimal RPi Performance with use of a SD card that has high random read/write times for the OS/System and a USB device with large capacity and high continuous read times for ROMs or content for KODI and other applications.
-Allow for re-flashing/image based upgrading without having to go through all the reconfiguration/customization (some would obviously still be necessary depending on what is changing)
-Eliminate the boot lag when syncing a lot of data
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