Parquet is not plain text (but that is an oxymoron anyways), but otherwise afaik it is pretty solid data interchange format supported by a number of tools alrea

Parquet is not plain text (but that is an oxymoron anyways), but otherwise afaik it is pretty solid data interchange format supported by a number of tools already. It doesn't have native formatting system, but it does allow arbitrary key-value metadata on columns so surely something could be cooked up with that.