Well I have downvoted lots of people on Hive, but that is because they are actively abusing the platform with plagiarism or excessive self votes. I do not generally do it for differences of opinion.
The community have to moderate the platform as nobody else is going to do it. That is how it was designed. There are finite rewards to share out each day and we want them to go where they are deserved. Of course opinions will vary on what deserves rewards and we have lots of people with strong/radical opinions. Your case of losing big rewards was down to someone thinking that rancho/haejin is not serving Hive well with their votes. I know that hurt, but I can see you are doing much better than most people.
You can argue about what deserves rewards, but it is not necessarily about how hard you work or what it cost to create something. I'm sure you can sell your art anyway. Hive is something new and radical. It is bound to have issues along the way. Why not just enjoy this extra income you would not have otherwise?
I don't think the downvote mechanism will radically change despite some people crying for change. Many of them will be like you and got the odd big DV after getting some big upvotes. I just saw someone complaining when they still made over $100 on the post.
Stay well.