first of all thx a lot for the good ideas: having negative curation rewards can be a great idea, or a bad one, i dont now yet, but it sounds interesting.
Honestly i dont even know yet if generally the curation reward is a good idea at all. Currently the most of the curation reward, just bots seems to get that vote always for the same posters or always after the same whale has post.

I think the biggest problem currently is, that people come from Spybook and reddit. And just think a upvote here is like a like in FB.

I outlined here some suggestions how we could solve that with having there different upvotes, so they would have to click like twice, before the post would get some money:

• If you press the first time up-vote you only rank the post higher, no extra payout.
• If you press the second time up-vote your vote is also considered for the payout.
• If you press the third time up-vote you indicate that this post is very very important for you.

Here the link to my suggestions, feel free to comment!
https://steemit.com/steemit/@arcurus/tagging-and-flagging-hidden-by-a-whale-how-to-evolve-further#@calamus056/re-arcurus-tagging-and-flagging-hidden-by-a-whale-how-to-evolve-further-20160807t184752235z