Currently the hole system is designed to generate exorbitant payouts.
Instead of downvoting exorbitant payouts, wouldn't it be better design the system so that it does not create these exorbitant payouts?

Right now the curation reward makes no sense at all. It just leads to upvote the same stuff from the same known people. This then makes the post trending which leads to even more votes.

What do we have to change?

I would suggest to drop the curation reward completely. If people understand that its their money they distribute they will take care for what to spent. Another solution would be to limit the curation reward per person per time period.

Second: Making the payout more linear would also reduce this over pay effect and on top of that would make the system much more simple and easy to understand. On top of that payouts could then be done instantly with every vote. Through steems blockchain transparency Self-voting could be easily detected and accounts flagged.

Third: Using a lottery like display of posts as default display option. The more votes the more chance to be chosen. A comment could also be counted as a vote with the users voting power.

If we implement these three changes the current self made over pay problem would most likely be solved.