The ability to flag particular fields that are created for the output

One thing that would be really helpful to speed up output creation or "discoverability" of fields that were INTENDED for the output would be to put a flag on the rule level.  Very often we are creating rules that are only intended to be consumed by other rules and then once consumed are intended to be for the output.  It would be really helpful to differentiate between rules that are meant for building up another rule vs something that is truly the final calculation that is going to end up in the output.