Here's a suggestion for the pipe-separated file format design.

Have all metadata consistently encoded with a "metadata." prefix.

Currently, some metadata are represented with "metadata.somekey" while others have no such prefix (e.g. "rule_id","rulereserve_nodes", "version_standard_url","ruledata_version","properties.id", category_applicable, in_effect.* ,linked_rules_or_lookups, normative_orientation., qualitative_weight.).

If we can consider all of this as metadata (the "data" being the logic table), I think a consistent notation for metadata is helpful:

• for machine processing, easier & more efficient to extract all metadata by matching on all rows prefixed with "metadata."
• for human auditability, easier to read and visual parse out the metadata section from the rest

As a general design principle, a "line-oriented design" would put all information necessary to understand a line into the line, such as a prefix string that distinguishes a line into the possible types / sections (metadata, header, input condition, output assertions, lookup record, etc). Such line-oriented design enable very flexible & efficient processing and trivial implementation of format-manipulation programs.