done
Can I simply delegate NS for seeds.bitshares.eu to ns2.afraid.org? I assume I need to set something up here so that they reply to seeds.bitshares.eu, dont't I?
Oops, I didn't notice you're already using afraid.org for bitshares.eu. This is probably not going to work then.
I have switched to another secondary, please replace the ns2.afraid.org RR with puck.nether.net. No further action required on your side, everything is set up.
Why not just add a CNAME record? NS is more heavy.
I try to avoid CNAME, it usually does not quite what you think it does. (And it isn't more heavy, the client must generate two queries in either case.)