I am the proud owner of a USG now and very much liking it.
I see from here DuckDNS configuration on USG that I could do away with the DuckDNS add-on in HA (hassio).
Intuitively it seems to make sense to take this load off of my HA Pi but perhaps the load is so tiny that I should just let sleeping dogs lie?
(I use the USG VPN so don’t need the LetsEncrypt bit of the addon)