Hi there! Blast from the past.
My original comments about ZTP paradigm for switches vs storage are overtaken by ansible, which uses the idea of idempotent states - so you tell ansible you want a netapp device configured a certain way, and it does what is needed to make that happen.
However, you need to be able to configure it, as you've noted.
So, where to go from there - new out of box nodes will present a cluster create/join on the CLI. This is also accessible via local subnet https API username admin and no password until the cluster is setup if dhcp is enabled on the subnet. So you should be able to use the cluster create API unauthenticated if you're on the same subnet.
Edit: As of 9.7, SSH to this LIF is apparently also supported, which would enable you to use "expect" scripts with ansible.
Hope this helps! Let me know - I haven't done it personally.