Been copying pihole.toml and the gravity db by hand on a cron.
Is Teleporter a full replacement for that, or does it skip anything?
Has anyone restored onto a fresh v6 install and had groups, clients
and local DNS records come back intact?
It looks something like this :
So you can pick the stuff you want to Backup or Restore AFAIK 
It is the opposite.
Your process is skipping some files.
Teleporter copy these files:
/etc/hosts
/pihole/dhcp.leases
/pihole/gravity.db
/pihole/pihole-FTL.db
/pihole/pihole.toml
And then import all your settings back, when you restore it.
Pi-hole v6 also can import old Teleporter v5 archives.