NFS : historically insecure by default. Don’t know about Kerberos making it secure but Kerberos does not look easy to configure.
sshfs : probably most easy to setup. Can be confusing with ownership and permissions sometimes.
Samba : solid but has a learning curve, even for a simple setup. For example, for a standalone Samba server omitting the Active Directory part, you need to know that in order to create a Samba user you must first have created a local user with the same username.