Yeah, I don't have the interest to get into it about this; but I find it (informally) inconsistent to take an ideological stance against NAT and not have a similar stance against NDP proxying. Networking is a lot cleaner when it can be reasoned about with a rudimentary grasp of graph theory where a network can roughly be seen as a complete graph and a node belonging to multiple complete graphs represents a destination in a routing table.
It is not challenging at all to use route(8) to subnet from a routed /48 or /56. How many subnets you want is up to you. If you want to only carve out a single /64 for all your hosts, then do so. You can then avoid DHCPv6 altogether and use rad(8) to send routing advertisements allowing clients to use SLAAC which is the much more popular way for clients to automatically configure IPv6 addresses. Also not sure where you heard that ICMP does not work with NAT. Surely you don't believe that. Go ahead and use ping(8) on any device that relies on NAT to talk to the outside world and witness how it "magically" works. ICMP uses the Query ID in lieu of a port number. Will NDP proxying work? Depending on what you want, sure just like NAT will likely work. Relying on a simple routing table is far more ideal. NDP proxying is also vulnerable to NDP cache DoS. You can use your favorite search engine to learn why NDP proxying is not as good as simple routes. If you want to use NAT or NDP proxying, then be my guest. It is one thing to not be willing to leave your ISP because you likely don't have many to choose from, but that is not the case for VPS providers. Challenge: reach out to the maintainers of popular NDP proxying daemons and inquire if they think NDP proxying is "clean" when compared to a simple routing table. In NDP proxying a host is responsible for responding to Neighbor Solicitation messages for IPs that don't belong to it. Hm, sounds a lot like NAT where a host uses its IP to masquerade the IPs of other hosts as opposed to traffic being handled by the actual host it was intended for.
