In reply to CW.

Sorry for being late to the party, been having some health issues :)

Yes, I hear you! It is a 100 times more frustrating to have to make these recommendations in the last moment (yes, these are/were recommendations although that's not very clear).

In your opinion what is better:
1. Have a brand-new, pretty complex, virtually untested API that leaves some "unanswered questions" about the way it works. Once added to WordPress it will have to be supported and maintained "forever".
2. Make the current patch into a feature plugin that follows the standard WordPress development practices. Then have it tested well, any bugs or inconsistencies fixed, and any questions answered before adding it to core.

Frankly I'd always go for 2. There is a reason feature plugins exist. This is the way to build better software.