Thank you. Looks like I'll just have to pay more. Any recommendations for a registrar?
I haven't needed to talk to them much, but one time I tried to add a .ninja domain, and there backend wouldn't handle it. I emailed them to report the problem at 4:49 p.m. I got an email at 7:09 p.m. the same day (2 hours 20 minutes later later) asking me to try adding it again. [1] When a free service fixes your problem in a few hours, they get +1 gold star from me.
[1] I just checked my email to look up the actual times. This was on Mar 15, 2017.
For example, you can run your own DNS server on a VPS or something, and HE will AXFR the zones from your VPS and serve them authoritatively.
This allows you to run a hidden master, for example, which I can imagine some HN folks being interested in.