I was using straight filesystem backups for a while, but I knew they could be inconsistent. Since then, I've setup https://github.com/prodrigestivill/docker-postgres-backup-lo..., which regularly dumps a snapshot to the filesystem, which regular filesystem backups can consume. The README has restore examples, too
I haven't needed to tune selfhosted databases. They do fine for low load on cheap hardware from 10 years ago.
I like consistent hashing (https://en.m.wikipedia.org/wiki/Consistent_hashing). When a hash table (or load balancing pool) needs to be resized, it usually reduces the number of keys (clients) that need to be remapped.
No need to give broader access