Part of the problem with the curation algorithm is that it's fairly strongly limited by the witnesses' calculation power and the number of blockchain operations necessary. There are ways that it could be improved, if those limits were reduced. Beyond that, it could also be improved by competition: if multiple entities and multiple priorities were driving the development of various curation algorithms, they would advance our knowledge of how to algorithmically reward the discovery of valuable content.
Both of these things can be achieved by decentralizing the calculation and distribution of curation, moving responsibility for it from the core blockchain to the posting interfaces (Steemit, @steempeak,
@busy, etc.) through the use of beneficiaries.
An interface would take a beneficiary payment, and run their own, off-chain calculation to determine the payouts for the voters, then send the rewards via transfer. This offers several advantages over any system with a set percentage of curation on the blockchain level:
This is sort of a hacked-up SMT-esque system that can be built on top of the current Steem today, as a proof-of-concept without any consensus change required. Many of the blockchain benefits depend on removal of the existing algorithm, but if the proof-of concept is demonstrated to be practical and effective, the base curation layer can be removed at a later date.
I didn't invent this, DTube did. I just noticed its potential to satisfy broad categories of stakeholders in the debate over curation rewards. 50/50 can happen if you want it to, so can 69/31, so can 100/0 if you like. User behavior can determine which are successful.