I virtually 100% agree with you here!

The figure I basically had in mind was 25% (or 2.5) per day. Obviously free downvotes have their downsides (toxicity, abuse etc) but they need to be enough to threaten the status quo. I feel that anything between 1.5-3.5 might be a reasonable guess.

So as a self voter and a conspicuous one at that, i'd expect that my farm posts would be nuked to oblivion when these changes are implemented by free downvotes. Good. I, and others like me, will get the message loud and clear and would likely not bother continuing farming, especially when curation is paying a decent amount (say 50%). We will likely not like the fact that others (self voters, vote sellers) get to benefit while we don't. So we'll use our free downvotes to take others down, and paid posts will be pretty high on that list.

The idea is to migrate profitable voting behavior from content indfferent to content reflective behavior. Imagine if the bid bots are now competing as curation services - it'll mean we'll no longer have a proof of brain dead blockchain.