Although it's not a format, the closest thing I have found is Postgres. You get well defined types that make life easier. They are stored efficiently in binary. And have a sensible text representation that means you can still read and write them by hand. I can store a PostGIS geometry with millions of verticies and still use text to create a point or read an envelope. Text formatting is hugely useful and benefits from standardisation. But that does not need to be built into the format.