I have mixed feelings about downvotes... There is a case for them, but I think that there is a problem with them being consequence free. Like all things, no risk of consequences leads to some odd behaviours... For instance, if you can crash a world economy (GFC) through consequence free actions and still be rich... Why not do it?

Proportionate downvoting is useful to signal disagreement... But what is chump change for one is a huge hit for another. It takes some level of wisdom to understand that instead of mashing 100%

SBI does well with long term support, and this is a model that is great for retention (the weakness of Steem). The curation projects are great, but having sugar hit means you need more of them...