I don't see where these are not one single problem. Everything is a file.
> A good standardized relational model format would be cool, and I'm sure such formats exist. Feels like we could do better than spitting out randomly (I.e per- tool) formatted data with so-so encoding support!
I'm actually currently trying to realize such a thing in Haskell, for usage in low traffic websites. There are obvious advantages in text DBs compared to binary DBs, for example versioning.
But I doubt we can do better than current Unix text files if we don't want to lock in to some very specific technology.
A very general format could solve more problems but as I said earlier I think the lack of comments in json makes it sub par as a config format for human editing.
If you need more commenting freedom or flexiblity, why not make another indirection and generate the data from some source which is tailored to your needs? After all, relational data is often not suited for manual input. It's meant for general consumption by computers.
For example, as a sysadmin, passwd / shadow / group is not enough to model my business objects directly. I keep my business data in a custom database, and generate the text files from that.
A sequence of tables in csv with decent encoding support would go a long way towards a good machine parseable relational text output.
It's really two separate discussions though: what is s good input/output format for Unix-like tools, and what makes a good format for a config file.