I've now gone and added some ntp servers from telstra, iinet and ntp.org. Good. Well now I have a number of ntp servers listed, hopefully it shall improve the situation.
I don't think ntpd has an option yet to autoreplace bad servers from DNS pools via future DNS queries. Either way all that's really needed is 2+1 to break ties, plus 1 or 2 for redundancy.
If system [ntp]date is set first, then under ntpd running for 15min+, if ntpq -np does not show one asterisk(*) in front
This will tell you status of peers.
TOR relay docs should perhaps include, for debian "add your isp's ntp servers, and possibly a few from ntp.org, to your /etc/ntpd.conf (and check this file is sane)".
You'd have to first figure out why it didn't work out of the box.
something I did to ntpd.conf (probably adding servers above the default debian entries which are: server 0.debian.pool.ntp.org iburst
The order doesn't matter. Though if DNS is not up before ntpd on boot, specified poolnames won't resolve and I think it's still a oneshot so only servers listed by ip would be loaded. see ntpq -np while listing a bogus hostname, a poolname, and an ip.