This is the best suggestion among all the comments here. I always thought if we will limit posts in steem in term of earning, it will be good. For example not more than $100 a post. For regular people who join steem and see those big numbers, they just don't believe that earning is possible at all. Also we will have less inflation that way. And if someone want to spend some money to promote his things, he will do his best to write quality post. Because if the earning will be limited, when he/she lose something from downvotes, he will not be able to add more money to that post. In this situation, all who are using bots, they will do their best to promote only quality posts.
I hope in the next hard fork, they will do something about that. We need to care a lot about the trending page. You can say, that's the face of steem. When someone outside of steem, take a look at steemit or any application, he/she should see our best content, but not the content that's promoted. We have so many good content creators who are not visible to the community at all.
Only this way steem price will grow and everyone will be happy about it !