NFS user and group

[Vortigern]

Dear All,
I've just installed TrueNAS on my microserver (home usage) and now I'd like to setup a NFS share. I have to Linux PCs that will connect to the NAS via NFS and I would like to restrict the access to the NFS only to those two machines. While doing so I came up with some questions I'd like to clarify before I continue:

1. Storage>Pools>Add Dataset>Advanced Options: which should be the "ACL mode" ?
2. Accounts>Users
   1. Shall I define a user to be assigned as the owner of the NFS share?
   2. Do I need more than one user?
   3. Shall the user(s) be assigned to "Maproot User" or "Mapall User"?
   4. Which is the importance of creating users/group for home usage?
3. Accounts>Groups
   1. Shall I define a group to be assigned to the NFS share?
   2. In case I need more than one user shall I add them to the same group?
   3. Shall the group be assigned to "Maproot Group" or "Mapall Group"?
4. I would like to simplify the mounting process so that it doesn't require a password to mount the NFS share
   1. is it enough to filter the access via "Sharing>NFS>Add>Advanced Options>Hosts" and enter the IP addresses of the two PCs + authorising only the local network (e.g. 192.168.1.0/24)?

Please note that it's fine to have both clients accessing the same shared folder (NFS share).

Thanks in advance for your support,
Vortigern