One of the main challenges for new servers on here is discovering content to interact with.
Relays speed up the discovery process, and allow even a single user server to automatically see a large part of the Fediverse.
There’s a new relay service by @firstname.lastname@example.org called FediBuzz Relay:
It allows servers to subscribe to custom relays based on tags or instances. (If you use this, can you let us know your experiences in the replies?)