Inclusion of data elements is based on "what do most systems do". Not all attribution elements are relevant (or at least commonly supported) for all resources. Nor are the same types, cardinalities or sometimes even names the same. We have instituted the use of patterns (Fivews, Definition, Request and Event) to try to drive additional consistency where implementer need does not drive divergence (and are tightening expectations for conscious divergence rather than spontaneous non-alignment). As well, mappings to patterns should aid those who desire a review of the resources that provides greater consistency. If you have thoughts on how to make these patterns and their mappings more useful for your use-case, feedback is welcome.