[daviddever23box]

It's a perfect opportunity to brush up on your {scripting language of choice} skills, though there are some pitfalls on macOS (e.g., not being able to set some preferences until another preference has been set).

Meta, I treat my devices like containers; assume that everything is ephemeral, and regenerate the environment on a frequent basis. Old stuff collects in iCloud as an archive, though anything live must be source-controlled (GitHub, Bitbucket et al).

By the way, as this unfortunately has to be said, credentials are NOT stored in source control. E-mail signatures and response tablets ARE.

As for system-wide backups, I don't do them (said the object storage guy); they're far too precious an approach to storage that ultimately should be better focused (live / archive / ephemeral). That said, the overlay approach that macOS takes should be more conducive to layered state, for those that DO backup.