Simply removing curation rewards would make the influence situation for the vast majority of users much better.
Right now, ~88% of the daily reward share distribution is given out by top 100 curators. That's 88% of all rewards for all posts being determined by 100 people. I'd put money on a bet that says the majority of the top 100 (at least 50) are curating primarily to gain a return on their investment.
The remaining ~4-5k users that cast votes every day make up the remaining 12% of the distribution..
Here's the kicker: posts are made visible based on the rewards they receive.
Add all these facts up and you're looking at a system where "popular" content is being driven by a small group of people motivated by profit. All while the vast majority of the population is under represented and lacking any meaningful influence.
If the incentive to curate content you think will earn a profit (for yourself) is removed, most likely some of the people curating will stop, which will reduce the influence of the top 100 and let others (with smaller balances) make a bigger splash in the rewards pool.
TLDR - Removing curation eliminates "for profit curation", which reduces whale activity, leaving more room for everyone else to make an impact.
If they were motivated by profit they would not bring so much crap to the top.
I think they are motivated by short term profit over the well being and popularity of the platform leading to long term profit.
I addressed this point here. It's important to remember that we're looking at first generation bots. In the long run, the bots that succeed will be the ones that promote steem's long term value. A short list of things bots can do that human curators can't/won't:
Of course there's more, but hopefully that gets the point across.
Whether it does it well or not at this point, I can tell you that the goal behind my own bot is to help raise steem's price by finding and supporting quality content. Curation rewards are a secondary consideration.
Update:* Reading through remaining comments. Up above, you asked about the early voting penalty before 30 minutes, and I don't think anyone answered. I couldn't respond to that comment because of the nesting limit, so here's a link - https://steemit.com/steem/@cryptomental/steem-internals-10-payment-reward-system-demystified
I guess you are probably right, those rewards create such bad incentives anyway, the faster they are gone the better. I think they should be distributed as inflation to steem power holders though not added to author payouts.
I wrote this comment about a month ago, when someone proposed removing curation rewards from the comment pool. It's also relevant here, even moreso:
"I don't really have a strong preference, but it is important to be aware that there are deep ethical issues associated with harvesting votes on comments without rewarding the voter. This is basically what all other platforms are already doing. One of the things that makes steemit different is its attempt to reward all parties who add value. Eliminating curation awards on comments seems like a step backwards. I recommend this video, where AI expert Jaron Lanier discusses the same phenomenon on other platforms. Here is a brief excerpt that captures the argument.
The only thing that has changed since I wrote that comment is that I have thought more deeply about it, and now I do have a strong preference. Eliminating curation rewards would be saying that curators should perform unpaid labor for the authors and the steem power holders. I disagree with that proposal.
This is probably the one valid argument I have heard in favor of keeping curation rewards. (IMO)
Wish I could take credit for it. That reminds me, I really need to set some time aside to read "Who Owns The Future." ; -) Seems like it would be very relevant to steemit.