My Debian Hypervisor do have a DE (GNOME) to be able to easily access virtual machines with virt-manager if I mess up their networking, my Debian VMs run CLI only though.
Regarding your last section I agree strongly - I only expose my vpn with no other incoming ports open. You also don't need to invest in a domain if you do it this way.
I don't mind helping my friends install their openvpn client and certificate and it's nice to not have my services bombarded with failed connection attempts.