We have some benefits to down votes with SteemFlagRewards, which has manual checks to prevent abuse. Any automatic system can probably be gamed.

I don't claim to have the answers. I do okay from rewards, but I see many getting frustrated whilst they see others raking it in (by whatever means). Reducing the benefits of self votes is okay unless people create proxy accounts.

The freedom of Steem is a great feature, but we see it being abused all the time. We can create as many accounts as we want (RCs permitting) so there could also be a landgrab of good names.