I think downvote button like on Reddit is NOT a good idea. I think it has a really bad effect there: If a post is controversal, or if many people THINK it's not important, it gets so many downvotes that the upvotes are cancelled out. I think this sometimes (or even often) happens with the most interesting and important posts.
A possibility were to show both the upvote and downvote count. This would be interesting, but I'm not sure if really benefical.
Although the third option is a good question, I will preffer to delete all bots.
In my opinion the downvote button is just a way of discourage people for launching all the little things they can launch. Not a good option.
That's a tough call! Personally, I'd go with the option of https://halloweensquishmallows.store/ that aligns best with my current goals and priorities.
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