Voting power is currently concentrated with a very small number of individuals. Many of these people do not have the time to properly curate. There are also just way too many posts for one individual to review.
Whales also may be interested in supporting more mainstream topics like photography, philosophy, scientific research, financial review, etc. but only have the knowledge and expertise to properly curate a smaller niche of topics.
This is important because there are a lot of investors out there who will want to buy in to the platform, but will not want to curate. Many whales just want to invest. Also, there are many good curators out there who don't have the Steem Power to make their curation profitable.
Building off the model that @smooth has already implemented, Steemit should allow whales to easily delegate their voting power to other users. This would allow people with a large amount of SP to 'hire' good curators to find quality posts. Good curators could get paid for the quality work that they do, without needing to make a large out of pocket investment. This will also increase the competition between human and bot curators.
A whale should be able to specify a user to delegate voting authority to, a percentage of their SP to delegate, and a percentage of the curation reward that they will share with the curator.
delegate_voting_power(user, percentage_sp, percentage_reward)
Whales will be able to hire teams of curators, and delegate appropriate stakes of SP and reward percentages based on performance. Good curators will be in high demand, and there will be a competition to do the best job curating. Many humans will be able to outperform bots, and whales will likely shift away from using bots/lists to hiring the best curators that they can find.
This will begin the race to the top.
