Looks great for an initial version. One thing to consider in the future - I like that 'hands-off' methodology with WUfB for CUs, where I can simply set deferral policies and know the updates will get approved automatically. Since the CUs are generally released on Patch Tuesday this gives us some predictability when the updates will come out and typically we would only have one reboot per month.
I am assuming that new drivers could drop in to Windows Update at any point during the month? If so it would be great to be able still be able to still use that automatic approval policy, but be able to align when they the updates would actually get offered to the devices to be at the same time as the CUs. That way they can hopefully be deployed at the same time and only require the one reboot.