I doubt it.
That’s not a bad idea. It might just point to a couple such guides that someone else is already maintaining.
EDIT: And finding one that has just 5 things to do and not 25 looks like it’ll be a challenge.
I think mostly this:
- configure apt for automatic upgrades and reboots
- installed fail2ban (though without password access for ssh, I’m not sure how necessary it is)
- see that ssh does not allow password logins (this is much easier now that Digital Ocean has a proper shell console that doesn’t require a password)