My take on this is that self-voting incentivizes investors to buy in to steem, and for that reason it should remain at least a while longer. A huge number of the people I see that upvote their own comment for $1+ have recently deposited a large amount from an exchange, so this can be seen as their ROI and a lot of them still go on to vote on other things as well. Eliminating self-voting entirely will result in less interest from people investing into the platform because they may not have much drive to be posting quality content or spending every day curating to get their returns. It would also be tremendously discouraging to the people that are actively investing based on the current self-vote mechanisms to suddenly have this restricted. An example is: https://steemit.com/@adept/transfers he has been heavily buying into steem, and upvoted my post alongside his own comment, so I am happy to have his vote and he gets some return on his recent large investments into the platform, it's good to have people buying on exchanges for this reason even if there is some downside to be seen here, because people buying STEEM/SBD is the only thing that gives them any value.

On the note of flags, I think there needs to be a log curve for their strength where smaller SP holders have a larger impact with their downvote but megawhales have somewhat less than they do right now. The reason is that someone can have 500 upvotes and a single whale can destroy their earnings or reputation because they hold more SP than the people upvoting, and in contrast a whale can post something that has 500 downvotes and still come out ahead. A log curve would skew this scenario more in favor of a popular vote while retaining the whales power to outvote more people than anyone else. It would also give a larger boost to the masses for filtering out spammers if the same change increased minnow flag power from its current value. I see a ton of spammy comments on various posts that get flagged by minnows but nothing changes until someone big comes along and uses their voting power to flag it, and like you said they hesitate to do that because in many ways it's a waste of their vote. So I think the log curve would push higher SP holders more toward upvoting than they already are while giving more power to filter spam to everyone else, which is in my opinion the best way to filter out the spammers since the big guys can't cover it all.

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sorry for the wall of text, I think the things I'm proposing needed some explanation for risk of sounding poorly planned. I actually have thought about this a lot and the self-voting thing plays into the game theory of steemit and is part of the reason people are so addicted to having more steem power, since it creates a snowballing effect it has a similar addiction mechanism to an idle game where there's never a good time to stop because you're almost always at your peak in terms of the rate of gain. The better way to address the people that are straight up exploiting it would be to rework curation rewards so that there's a better chance of having higher return by voting on other people's stuff, rather than the current system where only the top curators manage to exceed what you gain by self-voting.

Anyway, give it some thought guys. I think this is a really important topic that goes deeper than most people think, glad to have people delving into it.