Develop reference tags into more of a "feature"

In their current state, reference tags feel more like a developer-centric stop-gap than a fully considered feature of Craft.

I would love to see reference tags become more of a feature (selling-point of Craft) for CP users.

Rich Variables takes a step in this direction, but I'm imagining more core-level support.

Current issues

• 🐞 References tags are not multi-site, making them unusable, and/or broken in certain cases: https://github.com/craftcms/cms/issues/2956
• Many ref tags keyed by IDs, which are never exposed in the Craft CP (esp. globalset).
• Plugin developers cannot extend anything to their own ref tags/element types.
• parseRefs needs to be manually called on ANY field that may contain a ref tag for consistent behavior

Brainstorming

I'm imagining a field-level option "Parse Reference Tags" (alongside "Translation Method"), that would automatically parse a field's output for reference tags.

That option could then also be an indicator to the field to render some kind of "parse refs UI/selector" – basically an elementIndex modal where you could search through any elements and pop a ref tag into your field.

/cc @khalwat

Start by reviewing the reference tags documentation and the linked multi-site issue #2956, then compare the listed limitations with the proposed field-level option and selector UI. The issue does not name files or tests; completion would require an agreed core design covering multi-site behavior, plugin extensibility, parsing, and CP selection.