A bit of a reply to 
I think, first, that up and down votes are essential to a robust peer ostracism paradigm; the Steem white paper uses the terminology "downvote" numerous times. But the implementation uses flags, and there is a significant issue with whales having a lot of sway, but little granularity. I want to apologize to 
I think there is a way around this dilemma. Allow a vote to be placed with any amount of power the voter has available, from -max to +max Steem Power. Thus, a post a whale really likes, they can give full power to, and it will likely make a couple thousand. A post a whale likes some, they could drop a couple hundred power at, let it swim to the top, they still get paid for the early vote and hgh power relative to the rest of the commentors. And the same thing negatively: A Spam post, they vote negative full power, and get curator rewards for stopping it fast, a mildly repetitive post, they can drop a thousand power on, to keep it from getting too much money. An advanced feature might even allow a whale to try to peg a post to a dollar value, by applying the power as needed positively or negatively. A swarm of positive votes could still outweigh a single whale, and a whale could have as much or as little influence on a payout as they like. This would encourage whales to vote more on mediocre posts, which now they might not want to vote on because of their extreme influence.
Do not hide content based on downvotes, if a comment has -200000 SP downvoting, it's at the bottom of the pile and maybe the comment payout goes negative (perhaps to 10% of the comment pool total value, with a maximum of the poster's SD balance). So, there would be an incetive to not engage in flame wars, because it can cost you money.
Flagging, though, would ALSO remain, as a second tier. A flag would be an indication that the post is directly harmful and that it should be inspected by other curators for action. No need to flag a slightly repetitive post, or a comment with swearing. If you're a SJW, flag the "hate speech" all you want.
Because there has to be a way to counter improper flagging - for a curator to vote "nah, this flag was undeserved." There would be a "flagged" page, just like the trending page, where those interested could decide if they want to flag and/or downvote posts others have flagged.
Flagging could never go to positive power, but could go back to 0 power if enough curators decide it was undeserved.
Bad flagging: being a negative flagger on a post overwhelmingly flagged as not bad should COST the flagger. This should penalize jealousy flagging, spam flaging and other bad action - perhaps even taking not just SD from the shitflagger, but possibly costing them their SP.
Having a post which ends up negative flagged after this should also cost the posting person SP and SD.
I think this is a free market solution that would maintain the community rewards program, maintain the ability to give positive and negative feedback, but also not mix up "I dislike this" with "this is a problem."
