Many of these points are impossible if you think at the blockchain layer, now I really am not a dev or that technical but here's just some thoughts that come to mind:
- How? Only way would be to delegate to downvote accounts once downvote mana is delegatable and let users use their downvotes through a website/with memos and randomize the timers of when the downvote lands or include something like @smartsteem used to be where it would just pool all voting power and everyone who downvoted for content X give it an equal downvote at 6.5 days or sooner. Main point is that the author can't tell who directly downvoted them. This would still need some oversight for abuse.
- people also have private bots, some that with a few changes could be randomized a bit more to look manual, i.e. vote on this author between block 60-80 after post is out
- the early timing penalty was mainly to discourage bots and hasn't really served a lot of purpose ever since all bots adjusted to just becoming frontrunner bots, only disadvantage here is like I mentioned previously somewhere, think it was in my post as a response to jaki, it would only leave active curators and projects to go and find new content from new authors to get a decent reward for being the first to vote on it and might centralize a lot more stake in few curation projects, although the latter can of course be changed by creating more curation projects and them having more competition between eachother