You're right that the curation split won't (directly) attract readers who don't have Steem Power, but current incentives lean too heavily towards content creation, and not heavily enough towards content discovery. I believe that's part of the reason for the low engagement (unless one writes about Steem ;-). If voters do a better job at content discovery, it should draw uninvested readers as a 2nd-order effect.

Yes, there are a variety of possible third party work-arounds. But if we get the incentive structure right on the blockchain itself, then we shouldn't need third party hacks to make up for the deficiencies.