I've set up a nameserver for the PTRs for my hosts that are on the /64 that my tunnel provider has allocated to me, and it works fine, with one sort-of catch: its v6 only, which means it doesn't work for queries against nameservers that are v4 only, like the one at work (hides face in shame).
So, my question is: should I care? Its only broken for people that can't get to my network anyway, right? Or am I missing something?
You don't care...if I read your post correctly, the only thing this name server is going to authoritative for is your /64 or /48 network, which aren't IPv4.
In other words, the only people looking to you for RDNS are people looking for your network information, which is only IPv6