On: Time Machine in macOS 10.15.3 is very slow on firs...

[bayindirh]

It's not a Mac-centric solution but, all of my computers' crucial folders are sycned to each other via syncthing.

Desktop computers also back them up to another disk via backintime (an advanced backup tool built on rdiff).

This gives me realtime replication and two co-located backups. It's fire & forget kind of setup.