I'm concerned that any superlinear reward scheme will shift the reward balance even more towards the biggest whales and bid-bot-runners, it also shifts the balance further towards the more popular authors and away from the less-known authors.

Even now I'm often finding myself in a curationists dilemma - should I participate in the Keynesian beauty contest and give my upvotes to the most popular authors (maximizing my curation rewards), or should I send some rewards to some less-known people that actually posts good-quality-content?

I do have people in my feed that earns significant on each post they make, no matter the quality of the post. I have unfollowed one of them because I found myself quite disgusted of the high reward/quality he got on his posts (and, of course also because I didn't see much quality in his posts). The best way to gain curation rewards is to place carefully timed auto-votes on the most popular authors.