Need more flexibility in representing host networking
The current naive configuration, using explicit ip and ip6 host attributes (not related to the Ansible network device discovery process), is insufficient: for instance, it does not work in split networking setups as it cannot express properly the difference between "external IP for users" and "internal IP for other hosts".
It would be better to explicitly separate usage of IP addresses for external users, which are mostly confined to the dns role, and IP addresses meant for other hosts (used in the /etc/hosts service discovery mechanism). The latter could possibly benefit from closer integration with Ansible.