I've often read others wonder about this.

unfortunately there is not much resource out there on relay management.

but this might be starting to change, latest episode of nostr:npub1h8nk2346qezka5cpm8jjh3yl5j88pf4ly2ptu7s6uu55wcfqy0wq36rpev and nostr:npub1l2vyh47mk2p0qlsku7hg0vn29faehy9hy34ygaclpn66ukqp3afqutajft had some interesting interesting nunaces on how relays work and how we better structure/ choose them.

but I am still missing a comprehensive guide to the whole structure and dynamics of relays in the system.