some neat advantages that comes from using ε/os include (eventually) having the ability to (optionally) link your instance to #hyperboria and join dark fediverse.
PLEROMA.ISO will always be a super minimal system that only runs #pleroma.
to get the #mesh bits you'll need to swap out the disks and use TOMO.ISO instead. the on-disk config is the same, but some new menu options will appear in your admin console that can be used to enable #grid features.