Just thought I would share a really easy-to-read SSHd hardening guide linked to by:
Which is at; Secure Secure Shell
That is from 2015, but the only difference today from that I believe is the addition of some more ciphers and kex authorize thingies, which can be added on. BUT that guide is well written a good starting point for sure.
If you chat with reasonably technical people - of course every1 has an SSH client lols, so if you have a group of frenz in a tech circle, SSHd as an onion service is always an option, if not just encrypted P2P over Tor
SSH is kinda neat because it allows you to update/change your ciphers and such